PMTiles Concepts
PMTiles is a single-file archive format for pyramids of tiled data. A PMTiles archive can be hosted on a storage platform like S3, and enables low-cost, zero-maintenance map applications.

Concepts
PMTiles is a general format for tiled data addressed by Z/X/Y coordinates. This can be cartographic basemap vector tiles, remote sensing observations, JPEG images, or more.

PMTiles readers use HTTP Range Requests to fetch only the relevant tile or metadata inside a PMTiles archive on-demand.

The arrangement of tiles and directories is designed to minimize the amount of overhead requests when panning and zooming.

The current specification version of PMTiles is version 3, which you can read on GitHub.

https://docs.protomaps.com/pmtiles/#:~:text=PMTiles%20Concepts,read%20on%20GitHub.