Answers for "purpose of rest api"

rest api means

Let's break it into two components:

1) RESTful
2) API
An API is an interface through which one program or web site talks to another.
They are used to share data and services, and they come in many different
formats and types.

A RESTful API is one of the many possible ways that programs, servers, 
and web sites can share data and services. REST (Representational State Transfer
) describes the general rules for how the data and services are represented 
through the API so that other programs will be able to correctly request and 
receive the data and services that an API makes available

purpose of api

Knowing the purpose of the API will
set a firm foundation for you to
well prepare your test data for input
and output. This step also helps you
define the verification approach.
For example, for some APIs, you will
verify the responses against the
database; and for some others, it is
better to verify the responses 
against other APIs.