What is an API?

An API is a set of rules that lets two different computer programs talk to each other safely. It works like a menu in a restaurant where you pick what you want without going into the kitchen.

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~$ man api

What is an API?

Web Dev & SaaS gneurone encyclopedia
An API is a set of rules that lets two different computer programs talk to each other safely. It works like a menu in a restaurant where you pick what you want without going into the kitchen.

definition

An API (Application Programming Interface) is a defined set of rules, protocols, and tools that allows different software applications to communicate and exchange data.

Developers use APIs to access features or data from another service without needing to understand its internal code or database structure.

Think of an API like ordering at a fast-food counter: you tell the cashier your request using a simple menu, the kitchen prepares it behind the scenes, and you receive your food without ever entering the kitchen or learning their recipes.

key takeaways

  • APIs hide complex internal systems so developers only need to know the agreed request format.
  • Most modern apps and websites rely on APIs to fetch data from servers or third-party services.
  • Common API styles include REST, GraphQL, and gRPC, each with different strengths.
  • Security practices such as authentication and rate limiting are required when building or using APIs.
  • APIs make it possible to combine services, for example letting a weather app pull data from a forecast provider.

the 2026 job market

By 2026 API design and integration skills remain core requirements for backend, cloud, and SaaS engineering roles as companies continue shifting to microservices and connected platforms.

API Developer · $95,000-$135,000 (US) / $85,000-$115,000 (Canada) / £60,000-£85,000 (UK)Backend Engineer · $100,000-$150,000 (US) / $90,000-$125,000 (Canada) / £65,000-£95,000 (UK)Integration Specialist · $85,000-$120,000 (US) / $75,000-$105,000 (Canada) / £55,000-£78,000 (UK)

frequently asked questions

How do APIs work in practice?

A client sends a structured request to an endpoint, the server processes it according to the API rules, and returns data or confirmation in a standard format such as JSON.

What are the main types of APIs?

REST APIs use standard HTTP methods and are widely adopted for web services. GraphQL lets clients request exactly the data they need. SOAP is an older, more rigid XML-based standard still used in some enterprise systems.

Why do companies expose APIs to the public?

Public APIs let external developers build new tools and services on top of existing platforms, increasing reach and creating ecosystems around the core product.

Do I need coding skills to use an API?

Basic programming knowledge helps, but many APIs offer no-code tools, documentation, and client libraries that let beginners make requests with minimal setup.

courses to go further

Python Requests APIs
30 lessonsPython Requests APIsComing soon
$ cat ./full-guide.mdPython Requests APIs expliqué simplement (avec schémas et vrai code)read the guide →

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Auteur(s)

R

REHOUMA Haythem

Haythem Rehouma est un ingénieur et architecte IA et cloud, formateur et enseignant technique, avec un profil orienté IA médicale, AWS, MLOps, LLM/RAG et vision par ordinateur.