Learning Lab Home/Software Engineering/API (Application Programming Interface)

API (Application Programming Interface)

  • FAQ
  • Courses
  • Certifications
  • Careers
  • Jobs
  • Companies
  • Skills
  • Articles

What Is an API?

An API, or an application programming interface, acts as an intermediary between software and allows two applications to communicate and work with one another. APIs are critical to how software operates and are used by software engineers to enable the instantaneous sharing of data to provide seamless user experiences.


How Do APIs Work?

APIs function by passing information from a service provider to an application via an API endpoint. They are often a key component to interoperability in software development, often facilitating the transfer of data via request and response. 

APIs work by delivering a request to a system and sending the system’s response back to whatever made the request. This process allows for shared functionality allowing between one application and another.

A critical component of an API, known as the API endpoint, provides a specification by which the applications can communicate, thereby decoupling the consuming application from the infrastructure providing that API endpoint. As long as what the delivering requester follows the endpoint’s specifications, changes to the service provider’s infrastructure won’t alter how API-reliant applications receive data. This process facilitates flexibility between separate infrastructures or applications.

What Is an API? | Video: MuleSoft Videos


API Examples

A common example of APIs in use are applications accessed through a mobile device, such as a weather app, social media app, finance app or GPS app.

Applications, mobile or otherwise, work by connecting to the internet and sending data to a server. Upon receiving that data, the server will interpret and complete all possible actions requested by the application and return it to the source. That application will then receive, process and display the data  to the user in the way it is programmed. 

Let’s look at the weather app example. When a user opens the application, the API will send a request to the database to retrieve the current forecast based on the device’s location, date and time of day (which are also pulled with separate APIs). The database will receive that request, locate the necessary data and return it to the weather app, which will present it in the form of temperature and conditional readings. Many APIs function simultaneously within an application to deliver instantaneous results.

More From Built In Software ExpertsWhat Is Patch Management?


API and a REST API: What’s the Difference?

REST APIs are a subset of APIs that provide an architecture for API development. REST APIs facilitate faster build times and better adaptability. All APIs aren’t REST APIs, but all REST APIs are APIs. REST APIs are simply APIs constructed using REST architecture (representational state transfer).

APIs are considered RESTful only when requests are managed through HTTP. REST APIs often require headers and parameters to be passed in the API call as well. Common types of API requests include GET, POST, DELETE and PUT.

Other characteristics of the RESTful architecture include a stateless client-server connection (so each request is unconnected and secure), cacheable data and a uniform interface for maintaining a standard in how information is passed.


Expand Your API (Application Programming Interface) Career Opportunities

Learn how to work with APIs and other top software engineering skills with Udemy.



"Most Popular #1 SoapUI Test automation Course - "60,000+ students learning together with great collaboration"


What you'll learn:

  • At the end of this Course you…



Includes API, Web Services using REST, JSON, XML, HTTP, SOAP, OAuth, OpenID Connect, Postman and Python


What you'll learn:

  • Introduction to APIs and RESTful Web…



Build professional REST APIs with Python, Flask, Flask-RESTful, and Flask-SQLAlchemy


What you'll learn:

  • Connect web or mobile applications to databases and…



BRAND NEW COURSE- Advanced Postman tutorial to learn API /Web Services testing including CI/CD Integration from scratch


What you'll learn:

  • Understand how to…


API (Application Programming Interface) Certifications + Programs

Udacity’s software engineering certifications can give your resume the boost it needs to help you grow your career.

General Assembly’s Software Engineering Immersive is a transformative course designed for you to get the necessary skills for a coding role in three months. 

The Software Engineering bootcamp is led by instructors who are expert practitioners in their field, supported by career coaches that work with you since day one and enhanced by a career services team that is constantly in talks with employers about their tech hiring needs.


What you'll accomplish

As a graduate, you’ll have a portfolio of projects that show your knowledge of fundamental programming concepts, as well as experience with languages, frameworks, and libraries that employers demand. Throughout this expert-designed program, you’ll:

  • Create a front-end web application with modern JavaScript frameworks such as Angular or React.

  • Develop and deploy full-stack applications with in-demand technologies such as Ruby on Rails, Python with Django, and Express with Node.js.

  • Build secure full-stack applications by leveraging common design and architectural patterns like model–view–controller (MVC) and Representational State Transfer (REST).

  • Practice version control and collaborative software development with Git and GitHub.

  • Safely model and store data in SQL and NoSQL databases.

  • Consume and integrate third-party application programming interfaces (APIs) in an application.


Why General Assembly

Since 2011, General Assembly has graduated more than 40,000 students worldwide from the full time & part time courses. During the 2020 hiring shutdown, GA's students, instructors, and career coaches never lost focus, and the KPMG-validated numbers in their Outcomes report reflect it. *For students who graduated in 2020 — the peak of the pandemic — 74.4% of those who participated in GA's full-time Career Services program landed jobs within six months of graduation.  General Assembly is proud of their grads + teams' relentless dedication and to see those numbers rising. Download the report here.


Your next step? Submit an application to talk to the General Assembly Admissions team



Note: reviews are referenced from Career Karma - https://careerkarma.com/schools/general-assembly

4 months
10 hours

Learn back-end development with the Java programming language, one of the most popular programming languages in the world and one a majority of large enterprises rely on for their infrastructure.

4 months
10 hours

You’ll master the skills necessary to become a successful full stack developer. Learn how to build UI and UX, create APIs and server side business logic and develop the persistence layer to store, process and retrieve data.

4 months
10 hours

Looking to level up your API (Application Programming Interface) career? Subscribe to Built In.


Careers Related to APIs


Latest Software Engineering Jobs


Companies Hiring Software Engineers