The Largest
Repository of REST API
Knowledge
A comprehensive collection of terminology, practical guides, and code examples for designing, building, and maintaining professional-grade REST APIs.
What is API/OS Reference?
API/OS Reference is a comprehensive, free educational resource designed for developers, architects, and technical teams working with APIs. Every concept is explained clearly, with working code examples and security considerations where applicable.
{
"project": "API/OS Reference",
"terms": 160,
"guides": 12,
"categories": 10,
"languages": ["en", "es"],
"codeExamples": true,
"securityNotes": true
}Two Ways to Learn
Whether you need a quick reference or structured learning, we've got you covered.
Step-by-Step Guides
12 comprehensive guides taking you from HTTP fundamentals to advanced operations like observability and versioning. Each guide builds on the previous one.
- From beginner to expert
- Real-world examples
- Diagrams & visualizations
- Production-ready code
API Reference
160+ terms explained clearly and concisely. Precise technical definitions with code examples and security notes. Perfect for quick lookups.
- Organized by category
- Instant search
- Security notes
- RFC references
Explore by Category
10 categories covering all aspects of API design and development.
Your Learning Path
Regardless of your level, we have the right resource for you.
Ready to Master APIs?
Start with the fundamentals and progress to building production-grade APIs.