Like jQuery and YUI, MooTools offers nice, browser-independent shorthand for manipulating arrays, divs, spans and whatnot. My favorite part continues to be the custom library construction tool that lets you select the functions you want. Check some boxes and get an entirely optimised version of MooTools with just the functions you need and none of the bloat you don't. That's lightweight.
A number of other libraries offer newer features, for animation or data visualisation or server-side processing or other niches, or different ways of thinking about life in the browser. To get a close look at some of these newer options, I unpacked a number of libraries, wrote a few lines of code, instantiated a few objects and pushed some code through a few browsers.
Animation and HTML5 game engines
One of the stated goals of HTML5, at least for some groups, is to replace the Flash plugin, the gold standard for making sprites and letters dance across the screen. This change is slowly coming as the game industry and the presentation industry start to duplicate some of the sophisticated tools available in the Flash universe.
Mashi is an impressive example of how the sprites can be set in motion. It offers more than several dozen standard easing functions for moving sprites along a timeline.
If you like board games, you'll like the three dimensional, orthographic views of game boards from pp3disco. It takes just a few lines of code to set them up. CasualJS was designed to be just like ActionScript for those with plenty of Flash experience. The authors at Crafty obviously spent a good amount of time on their collision detection. Fruit Ninja fans can play Crafty's Fruit Assassin in their browsers.
In theory, nothing could be easier than sticking a video tag into your HTML. In practice, the behaviour of so many supposedly standards-compliant browsers is different enough that you'll be pulling out your hair if you try to support all of them. A number of good HTML5 libraries let you write standard HTML5 video tags that will be replaced with Flash or QuickTime if the browser isn't ready to handle your video.
The Video for Everybody project offers one of the better libraries, filled with features that operate in the background to smooth delivery on older browsers like IE8. And if Video for Everybody lacks the features you need, you can check out spinoffs like VideoJS and MediaElement.js, two projects that began with the Video for Everybody code before adding their own layer of events and controls.
VideoJS, for instance, makes it easy to change the appearance with a skinning layer. Some of the CSS files contain no images and thus minimise bandwidth costs, at least aside from the expense of delivering the video file. MediaElement.js offers a number of meta features, such as controlling captions and subtitles. One example illustrates how to let people choose the language in which the subtitles appear.
Big data visualisation
If the pundits are correct, there are many, many terabytes of data just waiting for people to come along and try to make sense of the bits. The first generation of HTML5 libraries was more focused on building forms and generating tables. Now a number of libraries are zeroing in on building charts and drawing graphs on the object.
You'll find plenty of great options for basic line graphs, bar graphs and combinations. Flot, Flotr, Raphael and JSCharts are just a few of the libraries that deliver solid renditions of the classics.
Some libraries go even further. The collection of demos for Protovis and its newer cousin D3, a name meant as shorthand for Data Driven Documents, show how sophisticated constructions like Voronoi diagrams and network graphs can illustrate more than the up and down of some value. Simile Widgets offers a different collection of views that are more focused on maps and timelines.
These projects illustrate how we're just beginning to come up with good ways of turning data into pictures that can help us absorb large volumes of information quickly and efficiently.
One of the more interesting niches for visualising data is drawing network graphs on the tag, a feature that's useful for displaying social networks and flowcharts. Canviz is a collection of rendering algorithms that turn a network into a picture using a mixture of straight and curved lines.
Draw2D takes a different approach. It creates full Visio-like drawings that link together polygons to illustrate a workflow.
Most of us will continue to use the big mapping libraries for standard jobs like showing street addresses. But what if you want to do something a bit different, such as change the rendering or fiddle with the layers in ways that the big libraries don't allow?
Tile5 can pull the mapping tiles from such sources as GeoCommons, then lay them out so that the user can shove them around just like the maps from Google, Mapquest or Yahoo. But there are other opportunities: The animation operation can change any of the parameters of the display. This is usually used for panning across the map and landing in one spot, not unlike the sequences in the Indiana Jones movies showing the plane flying over the map.
There's a surprisingly large collection of pixel-level operations available, including the ability to tweak the colours and apply filters like the ones used to blur images or compute edges. The basic library is now several years old, but Jacob Seidelin continues to create examples of how it can be applied, like this small web application called Filterrific.
Mobile libraries and browser books
As the mobile browsers begin to dominate the web, it becomes more and more important to package the information in a form that's easier to browse on smartphones and tablets. That's not so easy when the fingers are fat and the eyes can't focus on small fonts.
The iPad may be nice for reading, but its corporate masters demand a hefty percentage of the selling price for the privilege of being on the platform. A number of savvy programmers are writing text reading tools that fit in the browser, allowing publishers to deliver directly to the iPad without paying the Apple tax or going through the Apple censorship gauntlet.
Treesaver creates magazine-like layouts that allow you to flip through pages of text and images the old fashioned way. The code is small, just 25K, and released under both the MIT and GPL licence.
The Baker Framework is a similar project with a slightly different aesthetic approach. While Treesaver wants the text to flow into a convenient layout for the page, Baker assumes a constant width to make life easier for designers. Both of the tools make it possible to deliver booklike content directly from the web.
It's easy to forget that cookies can store 4,096 bytes of data. You would never want to store that much because each cookie is bundled together with subsequent trips to the server, that's why local databases were invented. Taking advantage of them is getting easier as new libraries simplify the details of interacting with the API.
Some of these libraries go a bit deeper. PHPLiveX, for instance, offers an integrated file uploading feature and some intelligent caching to improve performance. A number of libraries take this same approach, and of course some are more integrated with the standard libraries than others. jQuery-PHP is such an option for those who want a plugin for jQuery.
There are good server interaction libraries for almost every platform. Direct Web Remoting offers Java stack lovers the chance to call Java code on the server from the client with some security to prevent arbitrary calls. The code also includes a channel for the server to push some information to the clients that are logged in, a useful feature for broadcasting new information.
Blackbird is a standalone library that pops up a separate console window that looks quite elegant. You can set four levels of bugs and the user can turn the messages on or off. A profiler is ready to time the routines on the local browser.
Facing the future
Modernizr is mainly a collection of tests that checks to see what features are supported in the current browser. It's a simpler way to take advantage of the new while supporting the old. Most of the tests simply create a DOM object and see whether it accepts the commands.