API Architechture

In general terms, it acts as a messenger for applications, devices and databases. Suppose you are looking for a flight through an online travel booking site. It will ask you to enter the required details such as source, destination, and details of a trip or round trip in the prices you set.
An API architecture or format is one through which APIs are able to function. It is a set of the structures, rules, and restraints governing API operations.