# The best advantages of Storage area networks simplified
SANs are particularly helpful in backup and disaster recovery settings. Within a SAN, data can be transferred from one storage device to another without interacting with a server. This speeds up the backup process and eliminates the need to use server CPU cycles for backup. Also, many SANs utilize Fibre Channel technology or other networking protocols that allow the networks to span longer distances geographically.
That makes it more feasible for companies to keep their backup data in remote locations.
Utilizing a SAN can also simplify some management tasks, potentially allowing organizations to hire fewer IT workers or to free up some IT workers for other tasks. It's also possible to boot servers from a SAN, which can reduce the time and hassles involved in replacing a server.
Before the advent of SANs, organizations generally used direct-attached storage (DAS). As the name implies, direct-attached storage is directly attached to the server, residing either on the server or in a standalone storage device that is not part of a separate storage networking environment. Many smaller organizations continue to use DAS today because it offers lower upfront costs than deploying a SAN. However, for larger companies, the benefits of a SAN often outweigh the costs.
Alternatives Sometimes people confuse the term SAN with the term NAS, which stands for "network-attached storage." The key to distinguishing the two lies in the last term of each acronym: a SAN (storage area network) is an actual network, while NAS (network-attached storage) refers to a storage device, typically in an IP network. While SANs provide block-level storage for servers, a NAS device provides file-level storage for end users. For example, the mail application on your company servers might utilize a SAN to store all the messages, contacts and other data it requires; by contrast, an end user would use a NAS device to save files, such as word processing documents or spreadsheets. Operating systems see a SAN as a disk, while they see a NAS device as a file server.