Cache size refers to the allocated space on a device where temporary data is stored to improve performance and speed. In cloud storage and applications, cache stores frequently accessed files locally, reducing the need to download them repeatedly from a remote server. This speeds up file retrieval and optimizes bandwidth usage.

A common use case for cache size management is in cloud storage applications, where a local cache allows users to access recently used files quickly, even when working with large datasets. However, if the cache size is too large, it can consume unnecessary disk space, while a small cache may result in frequent downloads, slowing down performance. Optimizing cache settings ensures a balance between speed, storage efficiency, and system performance.