Tilepacks are binary files that encapsulate all the tiles for a specific tileset within a defined geographical area and zoom range. These files consist of a parent tile and its descendant tiles, each representing different levels of map detail over a particular geographic region. Tilepacks are organized based on predefined zoom ranges, with different ranges providing varying levels of detail, as detailed in the Mapbox Offline maps guide.
Each tilepack covers the area of its lowest zoom level map tile. The area that a tilepack covers can be deduced from the corresponding zoom level. For instance, if a tilepack contains tiles from zoom levels 11 to 14, the area it covers corresponds to the area of a single tile at zoom level 11, which would be larger than the area of a tile at zoom level 14, representing a broader geographical region with less detail.
Tilepacks are used to optimize the transfer, download, and storage of map data. They are more efficient compared to individual tiles as they have less per-tile and per-connection overhead. Think of a tilepack as a ZIP file, bundling many tiles into a single file, reducing the number of individual tiles that need to be downloaded and stored separately on disk.