types of file permission in linux.

What are the 3 three basic types of permissions?

There are three permission types: read, write, and execute.

Read: The capability to read contents. This is expressed as either the number 4 or letter r. 

Write: The capability to write or modify. This is expressed as either the number 2 or letter w. 

Execute: The capability to execute.

A file access definition can control access to data in specified tables and columns, or to tables and columns for which access is not granted explicitly. You define access permissions by creating an access list for a table, column, or the default.