vue-loader is a loader for webpack that allows you to author Vue components in a format called Single-File Components (SFCs). SFCs encapsulate the template, script, and style within a single .vue file, enhancing maintainability and organization in Vue.js projects. This popular tool streamlines the development process by handling pre-processing, hot-reloads, and scoping CSS, ultimately simplifying the creation of complex Vue applications. It is an integral part of most Vue.js workflows.