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function expression
function
optional name
parameters
  wrapped in ()
  zero or more names
  separated by a comma
body
  wrapped in {}
  zero or more statements

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hoisting in functions concern variables

The var statement gets spit into two parts:
  The declaration part gets hoisted to the top of the function, initializing with undefined.
  The initialization part turns into an ordinary assignment.
  
    var myVar = 0, myOtherVar;
    
  Expands into
    

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JavaScript is a protypal language but has syntax that is more similar to a classical language which can be confusing.

Function as module (using self-executing function ) is a way to do functions better in some instances.
Function as module safeguards against values being exposed b/c it limits scope:
(function () {
  var ...
  function ...
  function ...
}());

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var people = ['Jim', 'Bob', 'Jane', 'Jill'];
var welcomes = people.map(function(name) {
  return 'Hi' + ' ' + name + '!';
});

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// arr.forEach(callback[, thisArg])
// REMEMBER!! The forEach uses a function
// The forEach() method executes a provided function once per array element.
// The function can be written outside of the forEach() and called in the forEach() or 
// the function can be written inside of the forEach.
// You cannot break from a forEach().
// Each of the 3 code blocks below uses the same function written inside of the forEach(). 
// also these functions were between script tags in the .html file, if in ext file, they would need to be slightly modified using the this keyword
// For performance-critical scenarios (“hot paths,” tight loops, etc.), a classic for loop is better because the Javascript interpreter can better optimize it. This is also necessary if you need to break from the loop, which you cannot do with forEach.
// http://www.kraigbrockschmidt.com/2013/01/22/array-enumeration-javascript/

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..

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from: http://stackoverflow.com/questions/9329446/how-to-do-for-each-over-an-array-in-javascript

For Actual Arrays

(See "For Array-Like Objects" below for array-like objects.)

You currently have three options and will soon have two more:

Use forEach and related (ES5+)
Use a simple for loop

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for(in) loops through the enumerable properties of an object, not the indexes of an array

console.log('The primary use case for for(in) is to enumerate the properties of an object and will result in unexpected results if used with an Array');
  console.log('for(in) gives you the index positions of the items if used in the array and not an objecct:');
  console.log('the results below are from using a for(in) with var myNewArray = ["a", "b", "c", "d"]');
  
  var myNewArray = ["a", "b", "c", "d"];

  for (var i in myNewArray) {
    console.log('i', i);

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The input element with a type attribute whose value is "file" represents a list of file items, each consisting of a file name, a file type, and a file body (the contents of the file).
http://www.w3.org/TR/html-markup/input.file.html
http://msdn.microsoft.com/en-us/library/windows/apps/hh466145.aspx

Read Text Files Using the JavaScript FileReader
http://www.htmlgoodies.com/beyond/javascript/read-text-files-using-the-javascript-filereader.html
READONLY information for an individual file such as its name, size, mimetype, and a reference to the file handle. Adding the "multiple" attribute to the file input element (as in <input type="file" multiple/> will get you a list of files

<input type="file"/>
input always returns a FileList object

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function range(max) {
  var retVal = [];
  for (var i = 0; i < max; i++) {
    retVal.push(i * 2);
  }

return retVal;
}

var myArray = range(5);