What is Web API?

Web API is a specially created programming interface used for web servers or web browsers that is characterized by limitations on the client-side. In other words, web API doesn’t include implementing details of server or browser unless they are publicly accessible.

The work of any app is a very complicated process that is mostly built on permanent interaction among parts of the software. Access to data in the database and connection between client activity and websites are also important parts of any app or website’s functionality. Through that, web API is an extremely useful kind of programming interface. Now let’s look closer at it.

What is the Web API's Purpose?

In addition to the previous definition, it is possible to say that web API is a special framework that allows developers of digital products (software, program, website) to build, develop and maintain various RESTful services based on HTTP. The practical usefulness of web API is that this special interface allows applying any application on a distributed system and also gives services on different devices.

The Main Technologies of Creating a Web API

As a programming interface, web API is built by using programming languages. The most popular of them are:

Java;
PHP (provides free and open code);
C# (.NET) (provides a great variety of libraries);
NodeJs (guaranties the fast process of code performing);
Python.

The Principle of API’s Work

Web API is based on a specific sequence of actions. First, it receives requests from various devices used by clients (mobile, laptop, tablet) simultaneously; then, the request is sent to the webserver. As a result, the webserver works with this request by handling it. The result of that process is returned back to the user in the form of response to the primordial request. The duration of that process may differ, but the common practice is no more than 3-4 seconds.

In this operation, both server and client sides are engaged. The server-side is represented by a request-response message system, inputting of a resource identifier, and a combination of different server-side APIs. The client-side, on the other hand, is represented by standardized bunches created with the help of JavaScript programming language.

All the principles of API’s work, including web API, are followed according to API documentation, which is considered a technical description and instruction of effective usage of any kind of API.

Types of API and Their Differences

API is typically divided into four types which may differ according to some features.

Public API – an open type of API, the main feature of which is available for any person outside the business process.
Partner API – the second type which is defined by selected access mostly given to the outside developers.
Internal API – a type of API which is often called private and made with the intention of giving success only to the members of a project team or business.
Composite API – performs as a combination of several APIs with the purpose of building a sequence of operations, either related or independent.