chmod is Linux command used to change file permissions. chmod changes user, group and other read, write and execute permission. chmod 755 is popular use case for chmod . chmod 755 is generally used to make most of the operations without problem because it provides ease for system administrators while running applications.

755

755 can be separated as

• 7 user can read, write, execute
• 5 group can read and execute
• 5 others can read and execute

rwxr-xr-x

Another presentation form for 755 is rwxr-xr-x .

Sudo

We can also use chmod 755 with  sudo . In some situations we must use sudo because our current user rights will not meet required privileges.