An Application Program Interface (API) is a set of routines, protocols and tools for building software applications to complete a specialized portion of the workflow. For example, let's say you have a pricing list that must be updated in 300 stores around the world simultaneously. This can be done by using an API.
Content Manager allows for the use of these custom applications as a means of allowing you to contribute information, adjust workflow or monitor systems more efficiently. They are effective when automating repetitive, time consuming and error prone workflows, such as the store example we previously discussed.
There is no specific programming language that APIs must be written in, but they must be able to work with the UI.
Content Manager uses a full set of RESTful Web Service APIs that are supported by Scala.
The 1.x SOAP based API's are not supported by Release 11.00 of Content Manger. The 1.x API's were supplanted by the REST 2.x API's. For more information on this, please see this page (a username and password is required to view this document.)
A sample of the API documentation for Content Manager can be found here. The full version can be found by clicking on System in upper right hand corner of your Content Manager, then selecting Documentation, choose View API Documentation.