How to configure Linux Files Permissions?

Three types of permission read write and execute, Ever file and folder have three relations owner group and
others
-[ Read = r write = w execute = x ] [ owner = u group = g other = o ]
-[root@pc1 ~] # Ls -Ld /disk
-1= nature of object [d=dir -=file L=link]
-2= first three permission for owner [ rwx ]
-3= second three permission for group members [ r-x]
-4= third three permission for others [r-x]
-5= number of inodes contain by this directory
-6= owner of directory
-7= group of directory
-8= size of directory
-9= creating date of object
-10= name of object
-[root@pc1 ~] # Ls -L /disk
-Drwxr-xr – x 2 root root 4096 Jan 1 1988 dir1
-Drwxr-xr – x 2 root root 4096 Jan 1 1988 dir2
-Drwxr-xr – x 2 root root 4096 Jan 1 1988 dir3
-Changing permission = give write permission to other on /disk
-[root@pc1 ~] # chmod 0+w /disk
-Give read write and execute permission for group on /disk
-[root@pc1 ~] # chmod g+rwx /disk
-Assigning read writ and execute permission to user, group and other with single command
-[root@pc1 ~] # chmod u+rwx , g+rwx, o – rwx /disk
-Assigning different permission with different commands which separate with semicolon
-[root@pc1 ~] # chmod u+rwx /disk ; chmod g+rwx /disk ; chmod 0+rx /disk
-Using number system =----- [ Read = 4 ] [ Write = 2 ] [ Execute = 1 ]
-rwx=7
-r-x=5
----=0
-Assigning full permission to owner and no permission for group and others
-[root@pc1 ~] # chmod 700 /disk
-Assigning full permission for owner and group no permission for other
-[root@pc1 ~] # chmod 700 /disk
-Assigning full permission to all
-[root@pc1 ~] # chmod 777 /disk
-Assigning full permission for owner and read, and execute for group and others
-[root@pc1 ~] # chmod 755 /disk
-Assigning no permission for all
-[root@pc1 ~] # chmod 000 /disk
-Assigning sticky bit permission for other
-[root@pc1 ~] # chmod o+t /disk
-Assigning suid permission for owner
-[root@pc1 ~] # chmod u+s /disk
-Assigning sgid permission for group-[root@pc1 ~] # chmod g+s /disk