jQuery is a JavaScript library that, for many years, was the standard way to make web pages interactive. It let developers select elements, respond to clicks and load content without a page refresh, all with short commands that worked the same in every browser. In the 2010s, most of the web ran on it.
A fair analogy is a universal remote. Back when every device spoke a slightly different language, jQuery was the one remote that controlled them all with the same buttons. That mattered hugely when browsers behaved inconsistently. As browsers grew more uniform, the need for that remote shrank, and lighter tools like Vue.js took over for new work.
A big reason it spread was AJAX. jQuery made it trivial to fetch data in the background and update part of a page without reloading, something that used to take pages of fiddly browser-specific code. That one feature shaped how interactive sites were built for a decade, and its short $() syntax became so familiar that a whole generation of developers learned the web through it.
jQuery is far from dead, though. It still powers a large slice of the web, especially older WordPress sites and the plugins built around them. As one of the most widely used JavaScript libraries in history, it lingers in places you would not expect. Removing it carelessly can break a working site, because a theme or a third-party plugin may quietly call it under the hood.
At TopDevs we keep jQuery running where existing code relies on it, and reach for modern alternatives only when we rebuild a site from the ground up.
