A recent Lullabot podcast explained the use of web APIs to build mashups. Here's a general overview of the topic and the podcast.
Back at Clemson, circa 2002, we had a CompSci class where we discussed SOAP and web services as the future of the web. It made little sense in the context of the day. Now that it's here it makes a lot more sense.
If you've got 50 minutes of down time or travel and want a synopsis of where web services / web applications / APIs / mashups are at these days then I suggest the Lullabot podcast discussing the various technologies.
You'll want to skip over their normal blabbing and jump to 14:25 and listen until you reach the Drupal-centric portions around 1:06:45.
Acronyms are thrown about, but they explain each of the server-to-server and client-to-server methods in pretty normal language and include basic examples or current applications. Topics include:
Format standards mentioned, and others I've encountered in my travels, include:
Examples of popular mashup-able API services include sites like Amazon, Google (14 services and counting), Yahoo (Fire Eagle, Flickr, BOSS, and many more). Plus, the Programmable Web was mentioned in the podcast as a nice resource covering most of the available APIs out there.
Essentially, we're talking about open sourcing data. With APIs you're now able to read, insert, update and/or delete your own user generated content (contacts, calendars, blog posts, etc) or access previously proprietary data sets (stocks tickers, live weather, yadda yadda) from other websites. For instance, OrangeCoat now injects a contact and message directly into our Highrise contact management system when visitors use our web contact form.
Facebook and others are taking some heat for their semi-open APIs where data is either shared selectively, allowed only inside the walls, or legally limited in use. It will be interesting to see whether opening or hording data proves to be the winning strategy. The current thinking suggests while opening up your data may invite competition it may also boost deeper adoption, adding to the service's advantage.