Introduction

1. What This Module Covers

The storage module ended with an observation: a cache is a small, short-lived read model. This module develops that observation because caches are among the most common and most frequently misused infrastructure in the industry. They also appear in system design interviews more often than almost any other storage technique.

The basic idea is simple: keep frequently used data in fast storage. A cache is a small, fast copy of data whose authoritative version remains in a slower system