Yepnope

Its purpose is to speed up page load time.

Documentation on how to use it is included in the project's README file, but the programmer basically includes under "yep" the scripts he wants to load at one point, and under "nope" the scripts he does not need for that moment.

Features:

• yepnope.js is only 1.6kb - smaller than most and certainly a good size for its functionality set.
• yepnope.js is called a "resource loader" because it can work with both JavaScript and CSS.
• yepnope.js has a full test suite in QUnit that you can run in your set of supported browsers to make sure it works. (We run it via TestSwarm in every browser we can get our hands on)
• yepnope.js fully decouples preloading from execution. This means that you have ultimate control of when your resource is executed and you can change that order on the fly.
• The yepnope.js api is friendly and encourages logical grouping of resources.
• yepnope.js is modular. It has a whole system for adding your own functionality and a couple examples of how you might do that. (Prefixes and filters).
• The yepnope.js API encourages you to only load the resources that you need. This means that even when it's slower than another script loader, it still can come out on top, because you could avoid an entire resource.
• yepnope.js is integrated into Modernizr.
• yepnope.js always executes things in the order they are listed. This is a pro for some, and a con for others. We think it's a friendly default.
• yepnope.js has the capability to do resource fallbacks and still download dependent scripts in parallel with the first.
• yepnope.js always executes things in the order they are listed.

What is new in this release:

• Scripts with the same url don't reexecute, but their callbacks fire in the correct order.
• The complete function behaves much more like the callback function with respect to 'recursive yepnope'.
• CSS load callbacks were taken out by default and put in an official plugin. Too few people used it. Old code will still work, callbacks just fire immediately on CSS (unless css load plugin is included).
• Exposed yepnope.injectJs and yepnope.injectCss in order to give you direct access to the injection functions.
• Added the ability to use key/value pairs in prefixes.
• Added a builtin prefix for overriding the global yepnope.errorTimeout with a specific timeout per script. yepnope('timeout=5000!script.js');
• Smarten'd up detection of CSS files even if there are query parameters (without the use of the css prefix plugin).

Requirements:

• JavaScript enabled on client side

Limitations:

• It is not always the fastest. There are a number of other script loaders (such as labjs) that optimize different situations than yepnope.