Leaflet is an open-source JavaScript library for mobile-friendly interactive maps. It's lightweight, easy to use, and makes it simple for developers to build beautiful, intuitive, and user-friendly maps. With Leaflet, you can easily add markers, popups, and other map controls, as well as integrate with external mapping services like Google Maps and OpenStreetMap. Plus, Leaflet's API is well-documented and packed with lots of helpful resources, making it easy to get up and running quickly. With its simple yet powerful functionality, Leaflet is ideal for developers looking for a reliable and efficient way to create interactive maps.