The Twilio REST API allows you to query meta-data about your account, phone numbers, calls, text messages, and recordings. You can also do some fancy things like initiate outbound calls and send text messages.
Since the API is based on REST principles, it's very easy to write and test applications. You can use your browser to access URLs, and you can use pretty much any HTTP client in any programming language to interact with the API.
All URLs referenced in the documentation have the following base:
The Twilio REST API is served over HTTPS. To ensure data privacy, unencrypted HTTP is not supported.
Twilio Accounts have the following subresources. Click on a link to read the API documentation for accessing or modifying each resource.
We designed the Twilio API in a very RESTful way, so that your consumption of it is simple and straightforward. From Wikipedia:
REST's proponents argue that the Web's scalability and growth are a direct result of a few key design principles:
REST's client/server separation of concerns simplifies component implementation, reduces the complexity of connector semantics, improves the effectiveness of performance tuning, and increases the scalability of pure server components. Layered system constraints allow intermediaries-proxies, gateways, and firewalls-to be introduced at various points in the communication without changing the interfaces between components, thus allowing them to assist in communication translation or improve performance via large-scale, shared caching.
REST enables intermediate processing by constraining messages to be self-descriptive: interaction is stateless between requests, standard methods and media types are used to indicate semantics and exchange information, and responses explicitly indicate cacheability.
If you're looking for more information about RESTful web services, the O'Reilly RESTful Web Services book is excellent.