What is a storage area network and why might you use one?

What will be an ideal response?

A storage area network (SAN) is a high-speed, high-cost network storage solution that largely replaces locally attached drives on servers. SAN technology allows multiple servers to access an enormous amount of shared storage that appears as locally attached drives from the server and user's perspective. This level of centralized storage offers better reliability and fault tolerance than traditional storage methods. Additionally, because storage is shared among several servers, power requirements for maintaining these systems are lower than those needed to maintain several servers with their own locally attached storage.