juniorAPI Design
What is an API Key?
Updated Apr 28, 2026
Short answer
A unique identifier used to authenticate a user, developer, or calling program to an API.
Deep explanation
API Design at the junior level focuses on standards and communication. A unique identifier used to authenticate a user, developer, or calling program to an API. Following REST constraints ensures interoperability and ease of use.
Real-world example
A weather app fetching current temperature from a remote server.
Common mistakes
- Using GET for operations that modify data.
Follow-up questions
- What is a 201 status code?