On his blog today, Evan Sims has posted the first part on a series of tutorials about working with the Twitter API in PHP to create a simple easy application.
Since Twitter is all the rage these days, I thought it would be a great starting point to introduce you to the world of web APIs and how simple they really are to work with. Twitter, like most presencing services, has a very limited range of API calls because, well, it's a very simple service.
Before he starts, he takes a second to explain the parts of the application - what REST is, why he chose PHP and an overview of the communication between client and server. After that, it's on to the code - creating a simple socket with the fsockopen functionality (and friends) and an example of a message that is sent over the socket to Twitter (in this case, a "test" message to ensure things are working).