Which command is used to check the number of files and disk space used and the each user’s defined quota?

repquota command is used to check the status of the user’s quota along with the disk space and number of files used.

This command gives a summary of the user’s quota that how much space and files are left for the user. Every user has a defined quota in Linux. This is done mainly for the security, as some users have only limited access to files. This provides a security to the files from unwanted access. The quota can be given to a single user or to a group of users.