One of the main reasons for encryption is to keep private and sensitive data secure from unauthorized access. Laptops, for example, are frequently stolen and their contents have, in some well-publicized cases, been made public or put to harmful or illegal uses. Servers, on the other hand, aren't usually stolen, but they do have multiple users, and while the Linux permissions system can prevent unauthorized access, there are ways for hackers to bypass it, and they are constantly trying. For example, ifone can gain root access, either legally as a system administrator, or illicitly by exploiting unpatched software security vulnerabilities, read/write access to everything on the system is allowed. Or, ifa user is not careful with setting permissions, access via other users may be allowed unintentionally. Inall cases, access by anyone who does not have the proper keys can be prevented by encryption.
