How do I check permissions in Linux? To view the permissions for all files in a directory, use the ls command with the -la options. Add other options as desired; for help, see List the files in a directory in Unix. In the output example above, the first character in each line indicates whether the listed object is a file or a directory.
What are groups in Linux? In Linux, a group is a collection of users. The main purpose of the groups is to define a set of privileges like read, write, or execute permission for a given resource that can be shared among the users within the group.
What is the meaning of chmod 777? Setting 777 permissions to a file or directory means that it will be readable, writable and executable by all users and may pose a huge security risk.
How do I use chmod? To add world read and execute permission to a file using the symbolic mode you would type chmod o+rx [filename]. To remove world read permission from a file you would type chmod o-r [filename].