Leaflet.js

Leaflet is a leading open-source JavaScript library for mobile-friendly interactive maps. Weighing just about 42 KB of gzipped JS code, it has all the mapping features most developers ever need.

Leaflet is designed with simplicity, performance and usability in mind. It works efficiently across all major desktop and mobile platforms, can be extended with lots of plugins, has a beautiful, easy to use and well-documented API, and a simple, readable source code.

Key features include layers control, custom markers, popups, vector layers (polylines, polygons, circles), image overlays, GeoJSON support, and a powerful plugin ecosystem. It’s widely used for adding interactive maps to web applications without the complexity of larger mapping frameworks.