Qu'est-ce qu'un cache ?

A cache is a small, fast storage layer that keeps copies of frequently accessed data so future requests

can be served much more quickly. Instead of fetching data from a slower source (like a database,

disk, or remote server) every time, the system checks the cache first;

if the data is there (a “cache hit”), it’s returned immediately, and if it’s missing (a “cache miss”),

the system retrieves the data from the original source and stores a copy in the cache for

next time. Caches improve performance, reduce load on backend systems, and are used at

many levels—CPU, browsers, applications, and databases.