Request/Response

Request/response is the fundamental exchange of the web. A web browser sends a request asking for a page, and a web server replies with a response, usually the HTML and assets that make up what you see. Every page you load is made of many of these small back-and-forths.

Understanding this rhythm helps you reason about why sites feel fast or slow. Each request takes time, and trimming or reusing them, through caching for instance, is a large part of making a site quick.