File Permissions in Linux / Unix Environment - How to Read, Write & Execute?

The type of owners are represented as,

u - User/Owner

g - Group

o - Other

a - All

Lets say if you give the permission as "0123", that means

0 for - User/Owner

1 for - Group

2 for - Other

3 for - All

You can use the following symbolic to change the user permission.

"+" Adds a permission to a file or directory

"–" Removes the permission

"=" Sets the permission and overrides the permissions set earlier.

Here I mentioned the user permission types to anyone can use.

Number	Permission	Symbol
0	No Permission	-
1	Execute	-x
2	Write	-w-
3	Execute + Write	-wx
4	Read	r–
5	Read + Execute	r-x
6	Read +Write	rw-
7	Read + Write +Execute	rwx