Best Practices for Javascript

Use 4-spaces for indentation (because it's easier to be consistent with Python than it is to switch your editor back and forth).
Javascript variables names should always be camelCase (never snake_case).
Constant variables and configuration parameters should be in TITLECASE_WITH_UNDERSCORES.
Named functions should be declared like this var functionName = function() {}.
Event handlers should be named on + the name of the event generator + the event name, for example onDocumentLoad, onWindowResize and onGoButtonClick.
All global variables should be defined at the top of the file.
All variables should be constrained to the current scope with var.
Declare one variable on one line.
End all statements with a semicolon.
Use spaces after opening and before closing braces and brackets in array and object definitions, i.e. { foo: [ 1, 2, 3 ] } not {foo:[1,2,3]}.
Do not use spaces after opening or before closing parentheses, i.e. if (foo === true) { and not if ( foo === true ) {.
Put else statements on the same line as the if block's closing }.
When accessing properties of a data structure (such as one retrieved using getJSON) prefer bracket syntax (data['property']) to attribute syntax (data.property).
Very frequent property references (e.g. those inside loops) should be cached, i.e. var array_length = array.length;.
Use === rather than ==. (Why?)
Use single-quotes for strings.

For consistency, prefer the following libraries to others that perform the same tasks:

jQuery for DOM manipulation
Underscore.js for functional programming (where Underscore and jQuery overlap, i.e. each(), prefer Underscore)
Bootstrap for responsiveness
Moment.js for datetime handling
jPlayer for audio/video playback

jQuery references that are used more than once should be cached. Prefix these references with $, i.e. var $electris = $('#electris');.
Whenever possible constrain jQuery DOM lookups within the scope of a cached element. For example, $electris.find('.candidate') is preferable to $('.candidate').
Always use on, never bind, delegate or live. on should also be preferred to "verb events", such as click.
When an event needs to occur for elements which may not yet exist, use on in delegated/bubble mode, rather than binding and unbinding events as elements are created and destroyed. For example: $wrapper.on('click', '.item', onItemClick).
When using on for delegated/bubbled events, always use the nearest container div. Do not use $body to capture events from anywhere as this degrades performance.

Avoid anonymous functions as callbacks unless their contents are trivially simple.
When clarity of code matters most: use Underscore functions for loops.
When performance matters most: unroll Underscore loops into standard for loops.

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