REST API is a web service interaction style over HTTP, like ordering food online. Send requests (GET, POST, PUT, DELETE) and the server responds accordingly. Must follow principles like client-server architecture & statelessness.

Adjust OpenAI API params to fine-tune results: Temperature (0-2), Max Tokens (4096/16384), TopP (0-1), Frequency Penalty (0-2) & Presence Penalty (0-2). Experiment with combos for best results in your app.

k6 is used for performance testing in e-commerce, APIs, gaming & banking industries. It simulates traffic surges, tests API scalability & validates transaction reliability. Learn k6 scripting with JavaScript basics & explore advanced features.