Jacques Ledoux
Sep 2, 2018 · 1 min read

A user interface (UI) is a mean for an individual to communicate with a program. For this, the user must learn how to use the interface either by training or reading the documentation.

An application programming interface (API) is a mean for a computer program (aka application) to communicate with another application. For this, the programmer of the requesting program (consumer) must learn how to use the API of the responding program (provider), either by training or reading the documentation (specification in this case).

An API is a specification that provides information on how consuming programs can retrieve/send data from/to a providing program. Of course, for this to be possible, both applications must be coded to support the API either as a consumer or a provider.

It is worthed noting that this description and the one in this article both refer to a program to program interaction context. The term API is also used in many other more technical contexts, generally referring to the internal of a program such as code calling other code. For instance, a class, an interface or even a method may be referred to as an API. But no worries as when a conversation gets to this point, you are definitively in presence of coding geeks :-).

    Jacques Ledoux

    Written by

    Mature and experienced IT professionnal that returns to his karma which has always been business analysis and software development.