21 files changed, 585 insertions, 98 deletions

diff --git a/c.html.markdown b/c.html.markdown
index a8f71057..3d632eab 100644
--- a/c.html.markdown
+++ b/c.html.markdown
@@ -445,6 +445,17 @@ int main (int argc, char** argv)
   for (xx = 0; xx < 20; xx++) {
     *(my_ptr + xx) = 20 - xx; // my_ptr[xx] = 20-xx
   } // Initialize memory to 20, 19, 18, 17... 2, 1 (as ints)
+  
+  // Note that there is no standard way to get the length of a
+  // dynamically allocated array in C. Because of this, if your arrays are
+  // going to be passed around your program a lot, you need another variable
+  // to keep track of the number of elements (size) of an array. See the
+  // functions section for more info.
+  int size = 10;
+  int *my_arr = malloc(sizeof(int) * size);
+  // Add an element to the array
+  my_arr = realloc(my_arr, ++size);
+  my_arr[10] = 5;
 
   // Dereferencing memory that you haven't allocated gives
   // "unpredictable results" - the program is said to invoke "undefined behavior"
@@ -530,6 +541,29 @@ swapTwoNumbers(&first, &second);
 printf("first: %d\nsecond: %d\n", first, second);
 // values will be swapped
 */
+
+/*
+With regards to arrays, they will always be passed to functions
+as pointers. Even if you statically allocate an array like `arr[10]`,
+it still gets passed as a pointer to the first element in any function calls.
+Again, there is no standard way to get the size of a dynamically allocated
+array in C.
+*/
+// Size must be passed!
+// Otherwise, this function has no way of knowing how big the array is.
+void printIntArray(int *arr, int size) {
+    int i;
+    for (i = 0; i < size; i++) {
+        printf("arr[%d] is: %d\n", i, arr[i]);
+    }
+}
+/*
+int my_arr[] = { 1, 2, 3, 4, 5, 6, 7, 8, 9, 10 };
+int size = 10;
+printIntArray(my_arr, size);
+// will print "arr[0] is: 1" etc
+*/
+
 // if referring to external variables outside function, must use extern keyword.
 int i = 0;
 void testFunc() {
diff --git a/coldfusion.html.markdown b/coldfusion.html.markdown
index e2f0737d..70804a1e 100644
--- a/coldfusion.html.markdown
+++ b/coldfusion.html.markdown
@@ -1,14 +1,14 @@
 ---
-language: ColdFusion
+language: coldfusion
+filename: learncoldfusion.cfm
 contributors:
     - ["Wayne Boka", "http://wboka.github.io"]
-filename: LearnColdFusion.cfm
 ---
 
 ColdFusion is a scripting language for web development.
 [Read more here.](http://www.adobe.com/products/coldfusion-family.html)
 
-```ColdFusion
+```html
 
 <em>HTML tags have been provided for output readability</em>
 
diff --git a/csharp.html.markdown b/csharp.html.markdown
index 31c0417e..dfdd98de 100644
--- a/csharp.html.markdown
+++ b/csharp.html.markdown
@@ -913,6 +913,35 @@ on a new line! ""Wow!"", the masses cried";
 
         public DbSet<Bicycle> Bikes { get; set; }
     }
+    
+    // Classes can be split across multiple .cs files
+    // A1.cs
+    public partial class A 
+    {
+        public static void A1()
+        {
+            Console.WriteLine("Method A1 in class A");
+        }
+    }
+    
+    // A2.cs
+    public partial class A
+    {
+        public static void A2()
+        {
+            Console.WriteLine("Method A2 in class A");
+        }
+    }
+    
+    // Program using the partial class "A"
+    public class Program 
+    {
+        static void Main()
+        {
+            A.A1();
+            A.A2();
+        }
+    }
 } // End Namespace
 ```
 
diff --git a/es-es/ruby-es.html.markdown b/es-es/ruby-es.html.markdown
index 66a5d0fe..d8b67fe7 100644
--- a/es-es/ruby-es.html.markdown
+++ b/es-es/ruby-es.html.markdown
@@ -5,8 +5,18 @@ contributors:
   - ["David Underwood", "http://theflyingdeveloper.com"]
   - ["Joel Walden", "http://joelwalden.net"]
   - ["Luke Holder", "http://twitter.com/lukeholder"]
+  - ["Tristan Hume", "http://thume.ca/"]
+  - ["Nick LaMuro", "https://github.com/NickLaMuro"]
+  - ["Marcos Brizeno", "http://www.about.me/marcosbrizeno"]
+  - ["Ariel Krakowski", "http://www.learneroo.com"]
+  - ["Dzianis Dashkevich", "https://github.com/dskecse"]
+  - ["Levi Bostian", "https://github.com/levibostian"]
+  - ["Rahil Momin", "https://github.com/iamrahil"]
+  - ["Gabriel Halley", "https://github.com/ghalley"]
+  - ["Persa Zula", "http://persazula.com"]
 translators:
     - ["Camilo Garrido", "http://www.twitter.com/hirohope"]
+    - ["Erick Bernal", "http://www.twitter.com/billowkib"]
 lang: es-es
 ---
 
@@ -33,6 +43,8 @@ Tu tampoco deberías
 8 - 1 #=> 7
 10 * 2 #=> 20
 35 / 5 #=> 7
+2**5 #=> 32
+5 % 3 #=> 2
 
 # La aritmética es sólo azúcar sintáctico
 # para llamar un método de un objeto
@@ -55,8 +67,6 @@ false.class #=> FalseClass
 # Desigualdad
 1 != 1 #=> false
 2 != 1 #=> true
-!true  #=> false
-!false #=> true
 
 # Además de 'false', 'nil' es otro valor falso
 
@@ -70,14 +80,29 @@ false.class #=> FalseClass
 2 <= 2 #=> true
 2 >= 2 #=> true
 
+# Operadores lógicos
+true && false #=> false
+true || false #=> true
+!true #=> false
+
+# Existen versiones alternativas de los operadores lógicos con menor prioridad
+# Estos son usados como constructores controladores de flujo que encadenan
+# sentencias hasta que una de ellas retorne verdadero o falso
+
+# `has_otra_cosa` solo se llama si `has_algo` retorna verdadero.
+has_algo() and has_otra_cosa()
+# `registra_error` solo se llama si `has_algo` falla
+has_algo() or registra_error()
+
+
 # Los strings son objetos
 
 'Soy un string'.class #=> String
 "Soy un string también".class #=> String
 
-referente = "usar interpolacion de strings"
+referente = "usar interpolación de strings"
 "Yo puedo #{referente} usando strings de comillas dobles"
-#=> "Yo puedo usar interpolacion de strings usando strings de comillas dobles"
+#=> "Yo puedo usar interpolación de strings usando strings de comillas dobles"
 
 
 # Imprime a la salida estándar
@@ -119,15 +144,16 @@ status == :aprovado #=> false
 # Arreglos
 
 # Esto es un arreglo
-[1, 2, 3, 4, 5] #=> [1, 2, 3, 4, 5]
+arreglo = [1, 2, 3, 4, 5] #=> [1, 2, 3, 4, 5]
 
 # Arreglos pueden contener elementos de distintos tipos
 
-arreglo = [1, "hola", false] #=> => [1, "hola", false]
+[1, "hola", false] #=> => [1, "hola", false]
 
 # Arreglos pueden ser indexados
 # Desde el frente
 arreglo[0] #=> 1
+arreglo.first #=> 1
 arreglo[12] #=> nil
 
 # Tal como la aritmética, el acceso como variable[índice]
@@ -138,15 +164,25 @@ arreglo.[] 12 #=> nil
 
 # Desde el final
 arreglo[-1] #=> 5
+arreglo.last #=> 5
+
+# Con un índice de inicio y longitud
+arreglo[2, 3] #=> [3, 4, 5]
 
-# Con un índice de inicio y final
-arreglo[2, 4] #=> [3, 4, 5]
+# Invertir un arreglo
+a = [1, 2, 3]
+a.reverse! #=> [3, 2, 1]
 
 # O con rango
 arreglo[1..3] #=> [2, 3, 4]
 
 # Añade elementos a un arreglo así
 arreglo << 6 #=> [1, 2, 3, 4, 5, 6]
+# O así
+arreglo.push(6) #=> [1, 2, 3, 4, 5, 6]
+
+#Verifica si un elemento ya existe en ese arreglo
+arreglo.include?(1) #=> true
 
 # Hashes son los diccionarios principales de Ruby con pares llave/valor.
 # Hashes se denotan con llaves:
@@ -161,17 +197,16 @@ hash['numero'] #=> 5
 # Preguntarle a un hash por una llave que no existe retorna 'nil':
 hash['nada aqui'] #=> nil
 
-# Itera sobre un hash con el método 'each':
-hash.each do |k, v|
-  puts "#{k} is #{v}"
-end
-
 # Desde Ruby 1.9, hay una sintaxis especial cuando se usa un símbolo como llave:
 
 nuevo_hash = { defcon: 3, accion: true}
 
 nuevo_hash.keys #=> [:defcon, :accion]
 
+# Verifica la existencia de llaves y valores en el hash
+new_hash.has_key?(:defcon) #=> true
+new_hash.has_value?(3) #=> true
+
 # Tip: Tanto los arreglos como los hashes son Enumerable (enumerables)
 # Comparten muchos métodos útiles tales como 'each', 'map', 'count', y más
 
@@ -194,9 +229,15 @@ end
 #=> iteracion 4
 #=> iteracion 5
 
-# Aunque
-# Nadie usa los ciclos `for`
-# Usa `each`, así:
+# SIN EMBARGO, nadie usa ciclos `for`
+# En su lugar debes usar el método "each" y pasarle un block (bloque).
+# Un bloque es un fragmento código que puedes pasar a métodos como `each`.
+# Es símilar a las funciones lambda, funciones anónimas o `closures` en otros
+# lenguajes de programación.
+#
+# El método `each` de un Range (rango) ejecuta el bloque una vez por cada elemento.
+# Al bloque se le pasa un contador como parametro.
+# Usar el método `each` con un bloque se ve así:
 
 (1..5).each do |contador|
   puts "iteracion #{contador}"
@@ -207,10 +248,27 @@ end
 #=> iteracion 4
 #=> iteracion 5
 
-counter = 1
-while counter <= 5 do
-  puts "iteracion #{counter}"
-  counter += 1
+# También puedes envolver el bloque entre llaves:
+(1..5).each { |counter| puts "iteración #{contador}" }
+
+#El contenido de las estructuras de datos en ruby puede ser iterado usando `each`.
+arreglo.each do |elemento|
+  puts "#{elemento} es parte del arreglo"
+end
+hash.each do |llave, valor|
+  puts "#{llave} es #{valor}"
+end
+
+# Si aún necesitas un índice puedes usar "each_with_index" y definir una variable
+# índice.
+arreglo.each_with_index do |element, index|
+  puts "#{element} tiene la posición #{index} en el arreglo"
+end
+
+contador = 1
+while contador <= 5 do
+  puts "iteracion #{contador}"
+  contador += 1
 end
 #=> iteracion 1
 #=> iteracion 2
@@ -218,6 +276,19 @@ end
 #=> iteracion 4
 #=> iteracion 5
 
+# Hay una gran variedad de otras funciones iterativas útiles en Ruby,
+# por ejemplo `map`, `reduce`,  `inject`, entre otras. Map, por ejemplo,
+# toma el arreglo sobre el cuál está iterando, le hace cambios
+# definidos en el bloque, y retorna un arreglo completamente nuevo.
+arreglo = [1,2,3,4,5]
+duplicado = array.map do |elemento|
+  elemento * 2
+end
+puts duplicado
+#=> [2,4,6,8,10]
+puts array
+#=> [1,2,3,4,5]
+
 nota = 'B'
 
 case nota
@@ -234,6 +305,34 @@ when 'F'
 else
   puts "Sistema alternativo de notas, ¿eh?"
 end
+#=> "Mejor suerte para la proxima"
+
+# Los casos también pueden usar rangos
+nota = 82
+
+case nota
+when 90..100
+  puts 'Excelente!'
+when 80..100
+  puts 'Buen trabajo'
+else
+  puts '¡Reprobaste!'
+end
+#=> "Buen trabajo"
+
+# Manejo de excepciones
+begin
+  # código que podría causar excepción
+  raise NoMemoryError, 'Se te acabó la memoria'
+rescue NoMemoryError => variable_de_excepcion
+  puts 'El error NoMemoryError ocurrió', variable_de_excepcion
+rescue RuntimeError => otra_variable_de_excepcion
+  puts 'El error RuntimeError ocurrió'
+else
+  puts 'Esto se ejecuta si ningun error ocurrió'
+ensure
+  puts 'Este código siempre se ejecuta, sin importar que'
+end
 
 # Funciones
 
@@ -244,7 +343,7 @@ end
 # Funciones (y todos los bloques) implícitamente retornan el valor de la última instrucción
 doble(2) #=> 4
 
-# Paréntesis son opcionales cuando el resultado es ambiguo
+# Paréntesis son opcionales cuando el resultado no es ambiguo
 doble 3 #=> 6
 
 doble doble 3 #=> 12
@@ -259,7 +358,7 @@ suma 3, 4 #=> 7
 suma suma(3,4), 5 #=> 12
 
 # yield
-# Todos los métodos tienen un parámetro de bloqueo opcional e implícitp
+# Todos los métodos tienen un parámetro bloque opcional e implícito
 # puede llamarse con la palabra clave 'yield'
 
 def alrededor
@@ -274,6 +373,17 @@ alrededor { puts 'hola mundo' }
 # hola mundo
 # }
 
+# Puedes pasar un bloque a una función
+# '&' representa una referencia a un bloque
+def visitantes(&bloque)
+  bloque.call
+end
+
+# Puedes pasar una lista de argumentos, que serán convertidos en un arreglo
+# Para eso sirve el operador ('*')
+def visitantes(*arreglo)
+  arreglo.each { |visitante| puts visitante }
+end
 
 # Define una clase con la palabra clave 'class'
 class Humano
@@ -299,16 +409,26 @@ class Humano
     @nombre
   end
 
+  # La funcionalidad anterior puede ser encapsulada usando el método attr_accessor
+  # de la siguiente manera
+
+  attr_accessor :name
+
+  # Los métodos de tipo getter y setter también se pueden crear de manera individual
+  # de la siguiente manera
+
+  attr_reader :name
+  attr_writer :name
+
   # Un método de clase usa 'self' (sí mismo) para distinguirse de métodos de instancia.
   # Sólo puede ser llamado en la clase, no por una instancia.
   def self.decir(mensaje)
-    puts "#{mensaje}"
+    puts mensaje
   end
 
   def especie
     @@especie
   end
-
 end
 
 
@@ -328,6 +448,23 @@ dwight.nombre #=> "Dwight K. Schrute"
 # Llama el método de clase
 Humano.decir("Hi") #=> "Hi"
 
+# El alcance de las variables es definido por la manera en que las nombramos.
+# Las variables que inician con $ tienen un alcance global
+$var = "Soy una variable global"
+defined? $var #=> "global-variable"
+
+# Las variables que empiezan con @ tienen un alcance de instancia
+@var = "Soy una variable de instancia"
+defined? @var #=> "instance-variable"
+
+# Variables que empiezan con @@ tienen un alcance de clase
+@@var = "Soy una variable de clase"
+defined? @@var #=> "class variable"
+
+# Las variables que empiezan con letra mayuscula son constantes
+Var = "Soy una constante"
+defined? Var #=> "constant"
+
 # Las clases también son un objeto en ruby. Por lo cual, las clases también pueden tener variables de instancia.
 # Variables de clase son compartidas a través de la clase y todos sus descendientes.
 
@@ -371,7 +508,67 @@ end
 class Doctor < Humano
 end
 
-Human.bar # 0
+Humano.bar # 0
 Doctor.bar # nil
 
+module ModuloEjemplo
+  def foo
+    'foo'
+  end
+end
+
+# Al incluir un módulo sus métodos se comparten con las instancias de la clase
+# Al extender un módulo sus métodos se comparten con la clase misma
+
+class Persona
+  include ModuloEjemplo
+end
+
+class Libro
+  extend ModuloEjemplo
+end
+
+Persona.foo     # => NoMethodError: undefined method `foo' for Persona:Class
+Persona.new.foo # => 'foo'
+Libro.foo       # => 'foo'
+Libro.new.foo   # => NoMethodError: undefined method `foo'
+
+# Las llamadas de retorno (callbacks) son ejecutadas cuando se incluye o
+# extiende un módulo
+module EjemploConcern
+  def self.incluido(base)
+    base.extend(MetodosClase)
+    base.send(:include, MetodosInstancia)
+  end
+
+  module MetodosClase
+    def bar
+      'bar'
+    end
+  end
+
+  module MetodosInstancia
+    def qux
+      'qux'
+    end
+  end
+end
+
+class Algo
+  include EjemploConcern
+end
+
+Algo.bar #=> 'bar'
+Algo.qux #=> NoMethodError: undefined method `qux'
+Algo.new.bar # => NoMethodError: undefined method `bar'
+Algo.new.qux # => 'qux'
 ```
+
+## Recursos adicionales
+- [Aprende Ruby Mediante Ejemplo con Ejercicios](http://www.learneroo.com/modules/61/nodes/338) - Una variante de
+esta referencia con ejercicios en navegador.
+- [Documentación Oficial](http://www.ruby-doc.org/core-2.1.1/)
+- [Ruby desde otros lenguajes](https://www.ruby-lang.org/en/documentation/ruby-from-other-languages/)
+- [Programando Ruby](http://www.amazon.com/Programming-Ruby-1-9-2-0-Programmers/dp/1937785491/) - Una
+[edición antigua](http://ruby-doc.com/docs/ProgrammingRuby/) gratuita disponible en línea.
+- [Guía de estilo de Ruby](https://github.com/bbatsov/ruby-style-guide) - Guía de estilo creada por la comunidad.
diff --git a/git.html.markdown b/git.html.markdown
index f678f9d1..bedc9853 100644
--- a/git.html.markdown
+++ b/git.html.markdown
@@ -371,9 +371,12 @@ Pulls from a repository and merges it with another branch.
 # Update your local repo, by merging in new changes
 # from the remote "origin" and "master" branch.
 # git pull <remote> <branch>
-# git pull => implicitly defaults to => git pull origin master
 $ git pull origin master
 
+# By default, git pull will update your current branch
+# by merging in new changes from its remote-tracking branch 
+$ git pull
+
 # Merge in changes from remote branch and rebase
 # branch commits onto your local repo, like: "git pull <remote> <branch>, git rebase <branch>"
 $ git pull origin master --rebase
@@ -387,9 +390,12 @@ Push and merge changes from a branch to a remote & branch.
 # Push and merge changes from a local repo to a
 # remote named "origin" and "master" branch.
 # git push <remote> <branch>
-# git push => implicitly defaults to => git push origin master
 $ git push origin master
 
+# By default, git push will push and merge changes from
+# the current branch to its remote-tracking branch 
+$ git push
+
 # To link up current local branch with a remote branch, add -u flag:
 $ git push -u origin master
 # Now, anytime you want to push from that same local branch, use shortcut:
diff --git a/it-it/coffeescript-it.html.markdown b/it-it/coffeescript-it.html.markdown
index 16eb9bd4..31973369 100644
--- a/it-it/coffeescript-it.html.markdown
+++ b/it-it/coffeescript-it.html.markdown
@@ -4,6 +4,8 @@ contributors:
   - ["Luca 'Kino' Maroni", "http://github.com/kino90"]
   - ["Tenor Biel", "http://github.com/L8D"]
   - ["Xavier Yao", "http://github.com/xavieryao"]
+translators:
+    - ["Tommaso Pifferi","http://github.com/neslinesli93"]
 filename: coffeescript-it.coffee
 lang: it-it
 ---
@@ -59,34 +61,34 @@ matematica =
   quadrato: quadrato
   cubo:   (x) -> x * quadrato x
 #=> var matematica = {
-#  "radice": Math.sqrt,
-#  "quadrato": quadrato,
-#  "cubo": function(x) { return x * quadrato(x); }
-#}
+#     "radice": Math.sqrt,
+#     "quadrato": quadrato,
+#     "cubo": function(x) { return x * quadrato(x); }
+#   }
 
 # Splats:
 gara = (vincitore, partecipanti...) ->
   print vincitore, partecipanti
 #=>gara = function() {
-#  var partecipanti, vincitore;
-#  vincitore = arguments[0], partecipanti = 2 <= arguments.length ? __slice.call(arguments, 1) : [];
-#  return print(vincitore, partecipanti);
-#};
+#    var partecipanti, vincitore;
+#    vincitore = arguments[0], partecipanti = 2 <= arguments.length ? __slice.call(arguments, 1) : [];
+#    return print(vincitore, partecipanti);
+#  };
 
 # Esistenza:
 alert "Lo sapevo!" if elvis?
 #=> if(typeof elvis !== "undefined" && elvis !== null) { alert("Lo sapevo!"); }
 
 # Comprensione degli Array:
-cubi = (matematica.cubo num for num in lista) 
+cubi = (matematica.cubo num for num in lista)
 #=>cubi = (function() {
-#	var _i, _len, _results;
-#	_results = [];
-# 	for (_i = 0, _len = lista.length; _i < _len; _i++) {
-#		num = lista[_i];
-#		_results.push(matematica.cubo(num));
-#	}
-#	return _results;
+#	   var _i, _len, _results;
+#	   _results = [];
+#    for (_i = 0, _len = lista.length; _i < _len; _i++) {
+#      num = lista[_i];
+#      _results.push(matematica.cubo(num));
+#    }
+#    return _results;
 #  })();
 
 cibi = ['broccoli', 'spinaci', 'cioccolato']
diff --git a/it-it/elixir-it.html.markdown b/it-it/elixir-it.html.markdown
index f5d0c172..60301b1a 100644
--- a/it-it/elixir-it.html.markdown
+++ b/it-it/elixir-it.html.markdown
@@ -4,6 +4,8 @@ contributors:
     - ["Luca 'Kino' Maroni", "https://github.com/kino90"]
     - ["Joao Marques", "http://github.com/mrshankly"]
     - ["Dzianis Dashkevich", "https://github.com/dskecse"]
+translators:
+    - ["Tommaso Pifferi","http://github.com/neslinesli93"]
 filename: learnelixir-it.ex
 lang: it-it
 ---
@@ -379,6 +381,12 @@ spawn(f) #=> #PID<0.40.0>
 # Per passare messaggi si usa l'operatore `send`.
 # Perché tutto questo sia utile dobbiamo essere capaci di ricevere messaggi, 
 # oltre ad inviarli. Questo è realizzabile con `receive`:
+
+# Il blocco `receive do` viene usato per mettersi in ascolto di messaggi
+# ed elaborarli quando vengono ricevuti. Un blocco `receive do` elabora
+# un solo messaggio ricevuto: per fare elaborazione multipla di messaggi, 
+# una funzione con un blocco `receive do` al suo intero dovrà chiamare
+# ricorsivamente sé stessa per entrare di nuovo nel blocco `receive do`.
 defmodule Geometria do
   def calcolo_area do
     receive do
@@ -394,6 +402,8 @@ end
 
 # Compila il modulo e crea un processo che esegue `calcolo_area` nella shell
 pid = spawn(fn -> Geometria.calcolo_area() end) #=> #PID<0.40.0>
+# Alternativamente
+pid = spawn(Geometria, :calcolo_area, [])
 
 # Invia un messaggio a `pid` che farà match su un pattern nel blocco in receive 
 send pid, {:rettangolo, 2, 3}
diff --git a/java.html.markdown b/java.html.markdown
index c2c1a18b..38c9e490 100644
--- a/java.html.markdown
+++ b/java.html.markdown
@@ -7,6 +7,7 @@ contributors:
     - ["Simon Morgan", "http://sjm.io/"]
     - ["Zachary Ferguson", "http://github.com/zfergus2"]
     - ["Cameron Schermerhorn", "http://github.com/cschermerhorn"]
+    - ["Rachel Stiyer", "https://github.com/rstiyer"]
 filename: LearnJava.java
 ---
 
@@ -137,7 +138,7 @@ public class LearnJava {
         //
         // BigDecimal allows the programmer complete control over decimal
         // rounding. It is recommended to use BigDecimal with currency values
-        // and where exact decimal percision is required.
+        // and where exact decimal precision is required.
         //
         // BigDecimal can be initialized with an int, long, double or String
         // or by initializing the unscaled value (BigInteger) and scale (int).
@@ -184,8 +185,12 @@ public class LearnJava {
         // LinkedLists - Implementation of doubly-linked list. All of the
         //               operations perform as could be expected for a
         //               doubly-linked list.
-        // Maps - A set of objects that maps keys to values. A map cannot
-        //        contain duplicate keys; each key can map to at most one value.
+        // Maps - A set of objects that map keys to values. Map is
+	//        an interface and therefore cannot be instantiated.
+	//        The type of keys and values contained in a Map must
+	//        be specified upon instantiation of the implementing
+        //        class. Each key may map to only one corresponding value,
+        //        and each key may appear only once (no duplicates).
         // HashMaps - This class uses a hashtable to implement the Map
         //            interface. This allows the execution time of basic
         //            operations, such as get and insert element, to remain
diff --git a/javascript.html.markdown b/javascript.html.markdown
index 9c4f06fc..d408e885 100644
--- a/javascript.html.markdown
+++ b/javascript.html.markdown
@@ -149,6 +149,10 @@ someOtherVar = 10;
 // Variables declared without being assigned to are set to undefined.
 var someThirdVar; // = undefined
 
+// if you wan't to declare a couple of variables, then you could use a comma 
+// separator
+var someFourthVar = 2, someFifthVar = 4;
+
 // There's shorthand for performing math operations on variables:
 someVar += 5; // equivalent to someVar = someVar + 5; someVar is 10 now
 someVar *= 10; // now someVar is 100
diff --git a/json.html.markdown b/json.html.markdown
index 060e9c3d..cde7bc40 100644
--- a/json.html.markdown
+++ b/json.html.markdown
@@ -5,22 +5,30 @@ contributors:
   - ["Anna Harren", "https://github.com/iirelu"]
   - ["Marco Scannadinari", "https://github.com/marcoms"]
   - ["himanshu", "https://github.com/himanshu81494"]
+  - ["Michael Neth", "https://github.com/infernocloud"]
 ---
 
-As JSON is an extremely simple data-interchange format, this is most likely going
-to be the simplest Learn X in Y Minutes ever.
+As JSON is an extremely simple data-interchange format, this is most likely going to be the simplest Learn X in Y Minutes ever.
 
-JSON in its purest form has no actual comments, but most parsers will accept
-C-style (`//`, `/* */`) comments. Some parsers also tolerate a trailing comma
-(i.e. a comma after the last element of an array or the after the last property of an object),
-but they should be avoided for better compatibility.
+JSON in its purest form has no actual comments, but most parsers will accept C-style (`//`, `/* */`) comments. Some parsers also tolerate a trailing comma (i.e. a comma after the last element of an array or the after the last property of an object), but they should be avoided for better compatibility.
 
 For the purposes of this, however, everything is going to be 100% valid JSON. Luckily, it kind of speaks for itself.
 
-Data types supported by JSON includes: numbers, string, boolean, array, object and null.
-Supporting browsers are: Firefox(Mozilla) 3.5, Internet Explorer 8, Chrome, Opera 10, Safari 4.
-JSON file type for JSON files is ".json". The MIME type for JSON text is "application/json"
-Drawbacks of JSON include lack of type definition and some sort of DTD.
+A JSON value must be a number, a string, an array, an object, or one of the following 3 literal names: true, false, null.
+
+Supporting browsers are: Firefox 3.5+, Internet Explorer 8.0+, Chrome 1.0+, Opera 10.0+, and Safari 4.0+.
+
+File extension for JSON files is ".json" and the MIME type for JSON text is "application/json".
+
+Many programming languages have support for serializing (encoding) and unserializing (decoding) JSON data into native data structures. Javascript has implicit support for manipulating JSON text as data.
+
+More information can be found at http://www.json.org/
+
+JSON is built on two structures:
+* A collection of name/value pairs. In various languages, this is realized as an object, record, struct, dictionary, hash table, keyed list, or associative array.
+* An ordered list of values. In most languages, this is realized as an array, vector, list, or sequence.
+
+An object with various name/value pairs.
 
 ```json
 {
@@ -60,8 +68,18 @@ Drawbacks of JSON include lack of type definition and some sort of DTD.
     "comment": "check this out!"
   , "comma position": "doesn't matter - as long as it's before the next key, then it's valid"
   , "another comment": "how nice"
-  },
-
-  "that was short": "And, you're done. You now know everything JSON has to offer."
+  }
 }
 ```
+
+A single array of values by itself is also valid JSON.
+
+```json
+[1, 2, 3, "text", true]
+```
+
+Objects can be a part of the array as well.
+
+```json
+[{"name": "Bob", "age": 25}, {"name": "Jane", "age": 29}, {"name": "Jack", "age": 31}]
+```
diff --git a/julia.html.markdown b/julia.html.markdown
index c5089dc3..cba7cd45 100644
--- a/julia.html.markdown
+++ b/julia.html.markdown
@@ -117,11 +117,11 @@ catch e
     println(e)
 end
 
-# Variable names start with a letter.
+# Variable names start with a letter or underscore.
 # After that, you can use letters, digits, underscores, and exclamation points.
 SomeOtherVar123! = 6 # => 6
 
-# You can also use unicode characters
+# You can also use certain unicode characters
 ☃ = 8 # => 8
 # These are especially handy for mathematical notation
 2 * π # => 6.283185307179586
diff --git a/objective-c.html.markdown b/objective-c.html.markdown
index cf6bf780..f130ea0c 100644
--- a/objective-c.html.markdown
+++ b/objective-c.html.markdown
@@ -148,7 +148,13 @@ int main (int argc, const char * argv[])
     [mutableDictionary setObject:@"value1" forKey:@"key1"];
     [mutableDictionary setObject:@"value2" forKey:@"key2"];
     [mutableDictionary removeObjectForKey:@"key1"];
-
+    
+    // Change types from Mutable To Immutable
+    //In general [object mutableCopy] will make the object mutable whereas [object copy] will make the object immutable
+    NSMutableDictionary *aMutableDictionary = [aDictionary mutableCopy];
+    NSDictionary *mutableDictionaryChanged = [mutableDictionary copy];
+    
+    
     // Set object
     NSSet *set = [NSSet setWithObjects:@"Hello", @"Hello", @"World", nil];
     NSLog(@"%@", set); // prints => {(Hello, World)} (may be in different order)
@@ -682,7 +688,7 @@ addUp = ^(int n) { // Remove (int n) to have a block that doesn't take in any pa
     mutableVar = 32; // Assigning new value to __block variable.
     return n + outsideVar; // Return statements are optional.
 }
-int addUp = add(10 + 16); // Calls block code with arguments.
+int addUp = addUp(10 + 16); // Calls block code with arguments.
 // Blocks are often used as arguments to functions to be called later, or for callbacks.
 @implementation BlockExample : NSObject
 
diff --git a/php.html.markdown b/php.html.markdown
index 13cc83eb..cf9544b3 100644
--- a/php.html.markdown
+++ b/php.html.markdown
@@ -104,7 +104,8 @@ END;
 echo 'This string ' . 'is concatenated';
 
 // Strings can be passed in as parameters to echo
-echo 'Multiple', 'Parameters', 'Valid';
+echo 'Multiple', 'Parameters', 'Valid';  // Returns 'MultipleParametersValid'
+
 
 /********************************
  * Constants
@@ -117,8 +118,10 @@ echo 'Multiple', 'Parameters', 'Valid';
 // followed by any number of letters, numbers, or underscores.
 define("FOO",     "something");
 
-// access to a constant is possible by direct using the choosen name
-echo 'This outputs '.FOO;
+// access to a constant is possible by calling the choosen name without a $
+echo FOO; // Returns 'something'
+echo 'This outputs '.FOO;  // Returns 'This ouputs something'
+
 
 
 /********************************
@@ -159,9 +162,9 @@ echo('Hello World!');
 
 print('Hello World!'); // The same as echo
 
-// echo is actually a language construct, so you can drop the parentheses.
+// echo and print are language constructs too, so you can drop the parentheses
 echo 'Hello World!';
-print 'Hello World!'; // So is print
+print 'Hello World!';
 
 $paragraph = 'paragraph';
 
@@ -219,7 +222,11 @@ assert($a !== $d);
 assert(1 === '1');
 assert(1 !== '1');
 
-// spaceship operator since PHP 7
+// 'Spaceship' operator (since PHP 7)
+// Returns 0 if values on either side are equal
+// Returns 1 if value on the left is greater
+// Returns -1 if the value on the right is greater
+
 $a = 100;
 $b = 1000;
 
@@ -445,6 +452,16 @@ function parameters() {
 
 parameters('Hello', 'World'); // Hello | 0 - Hello | 1 - World |
 
+// Since PHP 5.6 you can get a variable number of arguments
+function variable($word, ...$list) {
+	echo $word . " || ";
+	foreach ($list as $item) {
+		echo $item . ' | ';
+	}
+}
+
+variable("Separate", "Hello", "World") // Separate || Hello | World | 
+
 /********************************
  * Includes
  */
@@ -712,6 +729,43 @@ use My\Namespace as SomeOtherNamespace;
 
 $cls = new SomeOtherNamespace\MyClass();
 
+
+/**********************
+* Late Static Binding
+*
+* /
+
+class ParentClass {
+    public static function who() {
+        echo "I'm a " . __CLASS__ . "\n";
+    }
+    public static function test() {
+        // self references the class the method is defined within
+        self::who();
+        // static references the class the method was invoked on
+        static::who();
+    }
+}
+
+ParentClass::test();
+/*
+I'm a ParentClass
+I'm a ParentClass
+*/
+
+class ChildClass extends ParentClass {
+    public static function who() {
+        echo "But I'm " . __CLASS__ . "\n";
+    }
+}
+
+ChildClass::test();
+/*
+I'm a ParentClass
+But I'm ChildClass
+*/
+
+
 /**********************
 *  Error Handling
 *  
@@ -721,15 +775,15 @@ $cls = new SomeOtherNamespace\MyClass();
 
 try {
     // Do something
-} catch ( Exception $e) {
+} catch (Exception $e) {
     // Handle exception
 }
 
 // When using try catch blocks in a namespaced enviroment use the following
 
-try { 
+try {
     // Do something
-} catch (\Exception $e) { 
+} catch (\Exception $e) {
     // Handle exception
 }
 
@@ -738,13 +792,13 @@ try {
 class MyException extends Exception {}
 
 try {
-    
-    $condition = true; 
-    
+
+    $condition = true;
+
     if ($condition) {
         throw new MyException('Something just happend');
     }
-    
+
 } catch (MyException $e) {
     // Handle my exception
 }
diff --git a/python.html.markdown b/python.html.markdown
index b939ebbe..42a52bcf 100644
--- a/python.html.markdown
+++ b/python.html.markdown
@@ -4,6 +4,7 @@ contributors:
     - ["Louie Dinh", "http://ldinh.ca"]
     - ["Amin Bandali", "http://aminbandali.com"]
     - ["Andre Polykanine", "https://github.com/Oire"]
+    - ["evuez", "http://github.com/evuez"]
 filename: learnpython.py
 ---
 
@@ -58,6 +59,12 @@ allow you to write Python 3 code that will run on Python 2, so check out the Pyt
 -5 // 3  # => -2
 -5.0 // 3.0 # => -2.0
 
+# Note that we can also import division module(Section 6 Modules)
+# to carry out normal division with just one '/'.
+from __future__ import division
+11/4    # => 2.75  ...normal division
+11//4   # => 2 ...floored division  
+
 # Modulo operation
 7 % 3 # => 1
 
@@ -165,6 +172,7 @@ some_var  # => 5
 some_other_var  # Raises a name error
 
 # if can be used as an expression
+# Equivalent of C's '?:' ternary operator
 "yahoo!" if 3 > 2 else 2  # => "yahoo!"
 
 # Lists store sequences
@@ -218,6 +226,17 @@ li + other_li   # => [1, 2, 3, 4, 5, 6]
 # Concatenate lists with "extend()"
 li.extend(other_li)   # Now li is [1, 2, 3, 4, 5, 6]
 
+# Remove first occurrence of a value
+li.remove(2)  # li is now [1, 3, 4, 5, 6]
+li.remove(2)  # Raises a ValueError as 2 is not in the list
+
+# Insert an element at a specific index
+li.insert(1, 2)  # li is now [1, 2, 3, 4, 5, 6] again
+
+# Get the index of the first item found
+li.index(2)  # => 3
+li.index(7)  # Raises a ValueError as 7 is not in the list
+
 # Check for existence in a list with "in"
 1 in li   # => True
 
@@ -309,6 +328,15 @@ filled_set | other_set   # => {1, 2, 3, 4, 5, 6}
 # Do set difference with -
 {1, 2, 3, 4} - {2, 3, 5}   # => {1, 4}
 
+# Do set symmetric difference with ^
+{1, 2, 3, 4} ^ {2, 3, 5}  # => {1, 4, 5}
+
+# Check if set on the left is a superset of set on the right
+{1, 2} >= {1, 2, 3} # => False
+
+# Check if set on the left is a subset of set on the right
+{1, 2} <= {1, 2, 3} # => True
+
 # Check for existence in a set with in
 2 in filled_set   # => True
 10 in filled_set   # => False
@@ -460,19 +488,19 @@ def pass_all_the_args(*args, **kwargs):
 # Function Scope
 x = 5
 
-def setX(num):
+def set_x(num):
     # Local var x not the same as global variable x
     x = num # => 43
     print x # => 43
 
-def setGlobalX(num):
+def set_global_x(num):
     global x
     print x # => 5
     x = num # global var x is now set to 6
     print x # => 6
 
-setX(43)
-setGlobalX(6)
+set_x(43)
+set_global_x(6)
 
 # Python has first class functions
 def create_adder(x):
@@ -516,6 +544,10 @@ class Human(object):
         # Assign the argument to the instance's name attribute
         self.name = name
 
+        # Initialize property
+        self.age = 0
+
+
     # An instance method. All methods take "self" as the first argument
     def say(self, msg):
         return "{0}: {1}".format(self.name, msg)
@@ -531,6 +563,23 @@ class Human(object):
     def grunt():
         return "*grunt*"
 
+    # A property is just like a getter.
+    # It turns the method age() into an read-only attribute
+    # of the same name.
+    @property
+    def age(self):
+        return self._age
+
+    # This allows the property to be set
+    @age.setter
+    def age(self, age):
+        self._age = age
+
+    # This allows the property to be deleted
+    @age.deleter
+    def age(self):
+        del self._age
+
 
 # Instantiate a class
 i = Human(name="Ian")
@@ -550,6 +599,16 @@ j.get_species()   # => "H. neanderthalensis"
 # Call the static method
 Human.grunt()   # => "*grunt*"
 
+# Update the property
+i.age = 42
+
+# Get the property
+i.age # => 42
+
+# Delete the property
+del i.age
+i.age  # => raises an AttributeError
+
 
 ####################################################
 ## 6. Modules
@@ -648,7 +707,7 @@ print say(say_please=True)  # Can you buy me a beer? Please! I am poor :(
 * [Automate the Boring Stuff with Python](https://automatetheboringstuff.com)
 * [Learn Python The Hard Way](http://learnpythonthehardway.org/book/)
 * [Dive Into Python](http://www.diveintopython.net/)
-* [The Official Docs](http://docs.python.org/2.6/)
+* [The Official Docs](http://docs.python.org/2/)
 * [Hitchhiker's Guide to Python](http://docs.python-guide.org/en/latest/)
 * [Python Module of the Week](http://pymotw.com/2/)
 * [A Crash Course in Python for Scientists](http://nbviewer.ipython.org/5920182)
diff --git a/python3.html.markdown b/python3.html.markdown
index a1125c73..2398e7ac 100644
--- a/python3.html.markdown
+++ b/python3.html.markdown
@@ -5,6 +5,7 @@ contributors:
     - ["Steven Basart", "http://github.com/xksteven"]
     - ["Andre Polykanine", "https://github.com/Oire"]
     - ["Zachary Ferguson", "http://github.com/zfergus2"]
+    - ["evuez", "http://github.com/evuez"]
 filename: learnpython3.py
 ---
 
@@ -216,6 +217,17 @@ li2 = li[:]  # => li2 = [1, 2, 4, 3] but (li2 is li) will result in false.
 # Remove arbitrary elements from a list with "del"
 del li[2]  # li is now [1, 2, 3]
 
+# Remove first occurrence of a value
+li.remove(2)  # li is now [1, 3]
+li.remove(2)  # Raises a ValueError as 2 is not in the list
+
+# Insert an element at a specific index
+li.insert(1, 2)  # li is now [1, 2, 3] again
+
+# Get the index of the first item found
+li.index(2)  # => 3
+li.index(4)  # Raises a ValueError as 4 is not in the list
+
 # You can add lists
 # Note: values for li and for other_li are not modified.
 li + other_li  # => [1, 2, 3, 4, 5, 6]
@@ -249,6 +261,8 @@ tup[:2]          # => (1, 2)
 
 # You can unpack tuples (or lists) into variables
 a, b, c = (1, 2, 3)  # a is now 1, b is now 2 and c is now 3
+# You can also do extended unpacking
+a, *b, c = (1, 2, 3, 4)  # a is now 1, b is now [2, 3] and c is now 4
 # Tuples are created by default if you leave out the parentheses
 d, e, f = 4, 5, 6
 # Now look how easy it is to swap two values
@@ -306,6 +320,11 @@ filled_dict.update({"four":4})  # => {"one": 1, "two": 2, "three": 3, "four": 4}
 # Remove keys from a dictionary with del
 del filled_dict["one"]  # Removes the key "one" from filled dict
 
+# From Python 3.5 you can also use the additional unpacking options
+{'a': 1, **{'b': 2}}  # => {'a': 1, 'b': 2}
+{'a': 1, **{'a': 2}}  # => {'a': 2}
+
+
 
 # Sets store ... well sets
 empty_set = set()
@@ -332,6 +351,15 @@ filled_set | other_set  # => {1, 2, 3, 4, 5, 6}
 # Do set difference with -
 {1, 2, 3, 4} - {2, 3, 5}  # => {1, 4}
 
+# Do set symmetric difference with ^
+{1, 2, 3, 4} ^ {2, 3, 5}  # => {1, 4, 5}
+
+# Check if set on the left is a superset of set on the right
+{1, 2} >= {1, 2, 3} # => False
+
+# Check if set on the left is a subset of set on the right
+{1, 2} <= {1, 2, 3} # => True
+
 # Check for existence in a set with in
 2 in filled_set   # => True
 10 in filled_set  # => False
@@ -439,7 +467,7 @@ with open("myfile.txt") as f:
 
 filled_dict = {"one": 1, "two": 2, "three": 3}
 our_iterable = filled_dict.keys()
-print(our_iterable)  # => range(1,10). This is an object that implements our Iterable interface
+print(our_iterable)  # => dict_keys(['one', 'two', 'three']). This is an object that implements our Iterable interface.
 
 # We can loop over it.
 for i in our_iterable:
@@ -528,19 +556,19 @@ x, y = swap(x, y)     # => x = 2, y = 1
 # Function Scope
 x = 5
 
-def setX(num):
+def set_x(num):
     # Local var x not the same as global variable x
     x = num    # => 43
     print (x)  # => 43
 
-def setGlobalX(num):
+def set_global_x(num):
     global x
     print (x)  # => 5
     x = num    # global var x is now set to 6
     print (x)  # => 6
 
-setX(43)
-setGlobalX(6)
+set_x(43)
+set_global_x(6)
 
 
 # Python has first class functions
@@ -589,6 +617,9 @@ class Human:
         # Assign the argument to the instance's name attribute
         self.name = name
 
+        # Initialize property
+        self.age = 0
+
     # An instance method. All methods take "self" as the first argument
     def say(self, msg):
         return "{name}: {message}".format(name=self.name, message=msg)
@@ -604,6 +635,23 @@ class Human:
     def grunt():
         return "*grunt*"
 
+    # A property is just like a getter.
+    # It turns the method age() into an read-only attribute
+    # of the same name.
+    @property
+    def age(self):
+        return self._age
+
+    # This allows the property to be set
+    @age.setter
+    def age(self, age):
+        self._age = age
+
+    # This allows the property to be deleted
+    @age.deleter
+    def age(self):
+        del self._age
+
 
 # Instantiate a class
 i = Human(name="Ian")
@@ -623,6 +671,17 @@ j.get_species()  # => "H. neanderthalensis"
 # Call the static method
 Human.grunt()    # => "*grunt*"
 
+# Update the property
+i.age = 42
+
+# Get the property
+i.age # => 42
+
+# Delete the property
+del i.age
+i.age  # => raises an AttributeError
+
+
 
 ####################################################
 ## 6. Modules
diff --git a/pythonstatcomp.markdown.html b/pythonstatcomp.html.markdown
index 78b62e33..78b62e33 100644
--- a/pythonstatcomp.markdown.html
+++ b/pythonstatcomp.html.markdown
diff --git a/r.html.markdown b/r.html.markdown
index 93751df5..8896c5b0 100644
--- a/r.html.markdown
+++ b/r.html.markdown
@@ -15,7 +15,8 @@ R is a statistical computing language. It has lots of libraries for uploading an
 # You can't make multi-line comments,
 # but you can stack multiple comments like so.
 
-# in Windows or Mac, hit COMMAND-ENTER to execute a line
+# in Windows you can use CTRL-ENTER to execute a line.
+# on Mac it is COMMAND-ENTER
 
 
 
diff --git a/ruby.html.markdown b/ruby.html.markdown
index 4e9f8aee..998b4bf7 100644
--- a/ruby.html.markdown
+++ b/ruby.html.markdown
@@ -41,6 +41,7 @@ You shouldn't either
 35 / 5 #=> 7
 2**5 #=> 32
 5 % 3 #=> 2
+5 ^ 6 #=> 3
 
 # Arithmetic is just syntactic sugar
 # for calling a method on an object
diff --git a/tmux.html.markdown b/tmux.html.markdown
index 49d1bba6..868302a8 100644
--- a/tmux.html.markdown
+++ b/tmux.html.markdown
@@ -38,7 +38,7 @@ then later reattached.
     lsp              # List panes
      -a              # List all panes
      -s              # List all panes in session
-     -t              # List app panes in target
+     -t              # List all panes in target
 
     kill-window      # Kill current window
      -t "#"          # Kill target window
diff --git a/whip.html.markdown b/whip.html.markdown
index 3faee98a..61c301a5 100644
--- a/whip.html.markdown
+++ b/whip.html.markdown
@@ -2,6 +2,7 @@
 language: whip
 contributors:
   - ["Tenor Biel", "http://github.com/L8D"]
+  - ["Saurabh Sandav", "http://github.com/SaurabhSandav"]
 author: Tenor Biel
 author_url: http://github.com/L8D
 filename: whip.lisp
@@ -93,13 +94,13 @@ null ; used to indicate a deliberate non-value
 undefined ; user to indicate a value that hasn't been set
 
 ;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;;
-; 2. Vairbles, Lists, and Dicts
+; 2. Variables, Lists, and Dicts
 
 ; Variables are declared with the `def` or `let` functions.
 ; Variables that haven't been set will be `undefined`.
 (def some_var 5)
 ; `def` will keep the variable in the global context.
-; `let` will only have the variable inside its context, and has a wierder syntax.
+; `let` will only have the variable inside its context, and has a weirder syntax.
 (let ((a_var 5)) (+ a_var 5)) ; => 10
 (+ a_var 5) ; = undefined + 5 => undefined
 
@@ -163,7 +164,7 @@ undefined ; user to indicate a value that hasn't been set
 
 (my_function 10 10) ; = (+ (+ 10 10) 10) => 30
 
-; Obiously, all lambdas by definition are anonymous and
+; Obviously, all lambdas by definition are anonymous and
 ; technically always used anonymously. Redundancy.
 ((lambda (x) x) 10) ; => 10
 
@@ -191,7 +192,7 @@ undefined ; user to indicate a value that hasn't been set
 (slice (.. 1 5) 2) ; => (3 4 5)
 (\ (.. 0 100) -5) ; => (96 97 98 99 100)
 
-; `append` or `<<` is self expanatory
+; `append` or `<<` is self explanatory
 (append 4 (1 2 3)) ; => (1 2 3 4)
 (<< "bar" ("foo")) ; => ("foo" "bar")
 
diff --git a/xml.html.markdown b/xml.html.markdown
index efc2340f..b95d6088 100644
--- a/xml.html.markdown
+++ b/xml.html.markdown
@@ -3,6 +3,7 @@ language: xml
 filename: learnxml.xml
 contributors:
   - ["João Farias", "https://github.com/JoaoGFarias"]
+  - ["Rachel Stiyer", "https://github.com/rstiyer"]
 ---
 
 XML is a markup language designed to store and transport data.
@@ -65,12 +66,12 @@ Unlike HTML, XML does not specify how to display or to format data, it just carr
 
 * Well-Formated Document x Validation
 
-A XML document is well-formated if it is syntactically correct.
+An XML document is well-formatted if it is syntactically correct.
 However, it is possible to inject more constraints in the document,
 using document definitions, such as DTD and  XML Schema.
 
-A XML document which follows a document definition is called valid,
-regarding that document.
+An XML document which follows a document definition is called valid,
+in regards to that document.
 
 With this tool, you can check the XML data outside the application logic.