Using Twitter to Build a SMS Service > The Twitter API
Because Twitter has already done the hard work of implementing an SMS service (not to mention picked up the tab), you can use its API to send and receive messages on your behalf.
The API conforms to the principles of REST, as does the architecture of the site in general. This is important because the official API does not yet support everything needed to make a seamless SMS service. This guide will fill in some of the missing pieces. The API is under ongoing development, so the functions we talk about here may have changed or may be part of the official API by the time you read this.