Common ones are OAuth2 for delegated access, JWT for encoded tokens, and API keys for client identification.
API specification files describe operations/endpoints. Tools parse and render documentation automatically from specs.
Either through a version number in the URL path, a custom header, or content negotiation by the client.
Popular choices are Node.js for lightweight real-time APIs, Java/.NET for robust enterprises solutions, and PHP due to its widespread web use.
Common IDEs are Postman for testing, VSCode for editing specs, and SoapUI for testing RESTful services during development.
