KML (Keyhole Markup Language) is an XML-based file format used to represent geographic data in applications like Google Earth, Google Maps, and other geospatial software. It allows users to annotate maps and globes with a wide variety of features, including placemarks, images, polygons, 3D models, and textual descriptions. KML files can specify locations, overlays, and other elements, making them ideal for sharing geographic information and creating custom map visualizations. The format supports hierarchical structures, allowing for complex and organized representations of geographic data. KML files are often used for displaying points of interest, creating routes, defining areas, and visualizing spatial data. They can also include metadata such as author information, timestamps, and descriptions. The format is widely supported and has become a standard for exchanging geographic data on the web. KML files are human-readable, making them relatively easy to create and edit manually, although specialized software is often used for more complex tasks.