UNIX provides several security provisions for protecting files and data:  File Permissions: File permissions control who is allowed to read, write, or execute a file. File permissions can be set for the owner of the file, the group that the file belongs to, and other users (also known as "others" or "world").  Access Control Lists (ACLs): ACLs are an extended version of file permissions that allow us to specify more fine-grained access controls for a file. With ACLs, we can specify permissions for specific users or groups, rather than just the owner, group, and others.  Encryption: Encrypting a file or data ensures that it can only be read by someone with the appropriate decryption key. This can be useful for protecting sensitive information, such as passwords or financial data.  It is important to note that these security provisions are not mutually exclusive, and we can use a combination of these measures to protect our files and data.