What is an API?

What is an API?
Currently, APIs are increasingly being used by Developers in the software development process, contributing to speeding up work progress.

Nowadays, the fact that software has been and is being developed without too much dependence on programming languages has contributed to promoting the increasing use of APIs more strongly than ever.

What is an API?

API (Application Programming Interface) is a very familiar synopsis for IT people.

To put it simply, APIs are intermediate protocols that connect and provide communication between many different applications and libraries.

It provides access to a set of frequently used functions, thereby, it is possible to exchange data between applications.

Put yourself in the situation when you are eating at any restaurant, the waiter (API) will receive your order requests and convey them back to the kitchen area (system) about what needs to be processed.

Finally, that waiter will give you feedback, specifically in this case, bringing the food that the kitchen area has finished to your table.

API can be applied to web-based system, operating system, database system, computer hardware, software library...

Using APIs can help developers speed up the software development process, creating convenience towards the ultimate goal of improving work efficiency.

Currently, most large companies build their own APIs for internal use or provide them to customers.

What is an API?

Applications of API

In web API

This is an API system used for a website platform, including server and browser.

Almost every website has a web API that allows us to connect and make updates to the database.

Data returned by the web API is usually in the form of JSON or XML over the HTTP/HTTPS protocol.

What is an API?

In operating system

Both Linux and Windows operating systems have a lot of separate APIs.

They provide API documentation in the form of specification of connection functions, methods and protocols.

They assist programmers in creating software and applications that can interact directly with the operating system easily.

What is an API?

In framework

These are APIs that describe and specify the desired actions provided by the libraries.

Any API will have many different implementations. At the same time, making it possible for programs written in one language to use libraries written in other languages.

What is an API?

What are pros and cons of the API?


  • Using open source code, works with any client that supports JSON and XML.
  • Connected anytime, just need the Internet.
  • All information provided by the API is very reliable, because the two-way communication needs to be confirmed in the transactions.
  • Fully supports RESTful functions.
  • Configuration is relatively simpler compared to WCF (Window Communication Foundation).
  • Delivering an extremely user-friendly experience.
  • Capable of fully responding to HTTP components such as URL, request, response header, caching, versioning, content format...
  • Considered as one of the best application architectures for devices with limited bandwidth such as smartphones, tablets...

What is an API?


  • It costs a lot to build, operate and modify.
  • Requires users to have in-depth knowledge.
  • It is easy to encounter security issues when the system is attacked.

What is an API?