Glossary · Internet & Web

Web Browser

A web browser is software that requests pages from web servers, interprets HTML, CSS and JavaScript, and displays the result to the user.

Updated October 6, 2026

A web browser is an application that fetches web resources over HTTP or HTTPS and renders them as interactive pages. Chrome, Safari, Firefox and Edge are common examples.

Why it matters

Browsers are the client side of the web, so your site is only as good as it looks and works in them. They enforce security rules such as HTTPS warnings, the same-origin policy and cookie handling, and they differ in which features they support. Testing in more than one browser catches layout and script problems early.

Example

When you open https://example.com, the browser looks up the domain, opens a connection, sends a request with headers such as User-Agent and Accept, receives HTML, then downloads linked CSS, JavaScript and images. It builds the page, runs scripts and paints it on screen.

Common mistakes

  • Testing only in your own browser and missing issues in Safari or mobile browsers.
  • Blaming the server for a problem caused by a cached page or an extension; try a private window first.
  • Confusing the browser with the search engine or the operating system.

Get notified when this term updates

Plus occasional practical tips on uptime and monitoring, nothing else. Unsubscribe anytime.

Keep reading

Glossary · Internet & WebCookie (HTTP Cookie)A cookie is a small piece of data a website stores in your browser and sends back with later requests, used for sessions, preferences and tracking.Glossary · SecurityCookie Prefixes (__Host- and __Secure-)Cookie prefixes are name prefixes that make browsers enforce extra rules, such as Secure and no Domain attribute, on that cookie.Glossary · SecurityHttpOnly CookieThe HttpOnly flag marks a cookie so that browser JavaScript cannot read it, which limits theft of session cookies through cross-site scripting.Guide · SSL & SecurityCookie Flags Explained: Secure, HttpOnly and SameSiteWhat the Secure, HttpOnly, SameSite, Domain, Path and cookie prefix attributes do, how to set them in common stacks, and how to debug cookies that go missing.7 min readGuide · E-commerceWooCommerce Checkout Errors: Troubleshooting Guide for Store OwnersDiagnose WooCommerce checkout failures step by step: caching, AJAX and REST errors, plugin conflicts, sessions, payment gateways, SSL and server limits.8 min readError fix · Browser errorsERR_CACHE_MISS: "Confirm Form Resubmission" in Chrome ExplainedERR_CACHE_MISS appears when Chrome needs data it no longer has cached, often after a form POST. Learn the visitor fixes and the developer cause.4 min read

This page is general information written by our editorial team and updated when documentation changes. Servers and providers differ, so test changes safely first. See our editorial policy and disclaimer.