Browsers

A web browser, or browser, is a software application for retrieving, presenting, and traversing information on the World Wide Web. It requests resources via the Hypertext Transfer Protocol, renders HTML and associated resources, executes client-side scripts, and provides a user interface for navigating pages. A browser typically acts as a user agent that renders content according to web standards and security policies.

Rendering engines: They interpret markup and layout pages. Historically, engines include Trident (older Internet Explorer), Gecko (Firefox), WebKit (Safari), and Blink (Chrome and many other Chromium-based browsers). Browsers may include multiple engines or one core engine with different features. Notable browsers include Chrome, Firefox, Safari, Edge, Opera. Many are built on open standards and contribute to ongoing development.

Core components: rendering engine, JavaScript engine, networking, UI, data storage, and extensions. Features include tabbed browsing, bookmarking, history, password management, autofill, private browsing, and developer tools. Security features include sandboxing, same-origin policy enforcement, cookie management, and HTTPS/TLS. Privacy controls and tracking protections vary by product.

Standards and compatibility: Browsers strive to implement web standards from WHATWG and W3C. Compatibility can vary; developers rely on feature detection and progressive enhancement. The ecosystem includes desktop and mobile versions, as well as embedded browsers and user agents in apps and devices.