File permissions help protect the file from unauthorized or malicious user accessing or deleting the file. There are three basic file permission available for a file and they are :
Read - Allows you to read the file.
Write - Allows you to read and write to file.
Execute- Allows you to execute the file.
File permissions can be set as needed to the user for a particular file. However, the owner of the file has full access to the file. The owner of the file is responsible for providing file permission to the user. When the user logs in and he tries to access the file he will be checked against the permissions set up for him by the owner.
