Machine-based interaction is a common feature of Web 2.0 sites like Digg, Facebook and Dilicious, and these days it goes well beyond simple web feeds. An application programming interface (API) is what allows programmers to write applications and widgets that interact with services on these sites. The API gives them web-based access to data and functions from such sites. For example using the GoogleMaps API one could pull data and mapping information from Google that enables users of a site to view an embedded map of the location of a business.
Although typically using an API does require some expertise in programming, many of the APIs which are being released by sites are well documented with good examples on how to implement them, WebAPI. This article also details many of the user created scripts which have been generated using the various API’s which will give end users something to play with too.
With over 2 million articles Wikipedia is a valuable resource, the Mediawiki API allows access to this content. Sites based on the MediaWiki API include Wikitravel, Wiktionary, and WikiNews.
The Upcoming API allows you to take data from the Yahoo site upcoming.org. It’s useful if you want current events information on your site.
Last FM uses the Audio Scrobbler API to gather information about music you listen to. It is also the source of many various “is currently listening to” plug-ins for various applications.
Ebay’s API is very comprehensive, and supports almost all major web scripting options, including flash and Ajax. It has a sandbox for testing scripts, and offers you sample script blocks which it calls widgets to help you getting started. Visit Widget Blog Ebay for some examples.
Everyone knows about Facebook, it’s a hugely successful social networking site, that my girl friend assures me is very addictive. The site has loads of code samples, application creation guides and libraries for developers to play with. As Facebook is completely driven by user generated content it has a huge market of users just waiting to get their hands on fresh content, so for those that have the skill the Facebook API is a goldmine. Visit Mashable to read 10 awesome things built on the Facebook API.
As you may already know Feedburner is an RSS feed creation tool. The API gives developers a few toys to play with, the best of which is the Feedflare API which allows you to add new functionality onto Feedburner feeds.
The Google Search API Is a AJAX Search API that lets you put Google Search in your web pages with JavaScript. Google gives you some very useful examples of sample code to use.
You may not believe it , but the Yahoo search API is actually more popular than the Google alternative. You can use it to create a simple spell checking tool or site wide search widget… useful stuff
The API for Microsoft’s portal contains a whole heap of different APIs for different MS services. Here is some of the applications that have been created using the API, Windows Live API list, which includes content ranging from Halo 3 user guides to major league baseball videos.
With the AJAX Feed API, you can download any public Atom or RSS feed using only JavaScript, and easily mash up feeds with your content, and each other. It is super fast and is the quickest way to display real time RSS content on your site. Dynamic Drive’s gAjax RSS Feeds Displayer is a great example of a script created from this API.
Using the Digg API you can access individual stories, comments, or data on particular user activities. For some examples of the Digg API is action check out: 7 awesome things built on the digg API, Who’s digging You and Digg Comment Spy.
Although the Delicious API is not as complex or comprehensive as most of the other APIs featured, it is so simple, you can see results just by typing a URL into your browser. You can also write data to Delicious such as adding bookmarks or renaming tags. for example:
http://del.icio.us/api/posts/add?description=Pingable&url=www.pingable.org
..would add Pingable as a bookmark in to your delicious account after a username and password challenge. More detail at: Quick Online Tips.
The Google Maps API is probably the most implemented API on the net. It is used in applications such as Google flight simulator, dating sites, and for finding local auctions.
The Flickr API gives two way access to the site and some of its features and photos. Tasks that can be completed using the API include creating new sets, editing comments, changing photo notes, as well as pulling existing data from the site. Here is some examples of the Flickr API in action.
A very popular Number 1, because the YouTube API is both simple, and purely limited only by your imagination. Data which can be pulled from YouTube includes: Video titles, rating, length, tags, url, your favorites, your friend list and the thumbnail location. For an example of the YouTube API in action check out : CoverPop, and you may also want to check out: A YouTube and Google Map Mashup.
Other API resources: GotAPI , API finder, Mashery and a full list of Google APIs.
Digg and flickr icons from: ilemoned.com Web 2.0 Services Icons
Some of the content in this article was inspired by “The Top 20 APIs for your site” article in issue 167 of .net magazine.