Application programming interface

An Application Programming Interface (API) is a set of functions, procedures, methods or classes used by computer programs to request services from the operating system, r systems, acting as a retrieve the necessary data the user is requesting from the system.

Main types of web APIs:

• Open APIs - I edited this thing here, so ....
• Partner APIs - available to strategic business partners; they are exposed to a public API developer portal.
• Internal APIs - available to a company's internal development teams; they are exposed to a private API developer portal.
• Composite APIs - are a sequence of tasks bundled into a single API call.

Types of API include web services API like the Twitter API, which allows programs to use the API to receive updates on tweets.