API, for code implementing (NOT using) an Application Programming Interface. A program's API defines the proper way for a developer to request services from that program, site and/or service.

API, for code implementing an Application Programming Interface. A program's API defines the proper way for a developer to request services from that program, site and/or service. Do NOT use this tag if the code simply uses an already existing API. This tag is purely for questions which implement one in the question itself.

For using existing API, see if a tag is already created here. Keep in mind not every API needs its own tag. Questions about the Stack Exchange API can be tagged with .