chmod function to change the permissions mode in linux/unix. If you use the chmod 777 or 755 using octal mode. Actually, a number above the sum of the symbol mode.
symbol mode radio scripts free
r = read = 4 -> permissions for the right to read
w = write = 2 -> permissions for the right to write
x = execute = 1 -> permissions for the right to execute/run the executable file
so if 777 = rwxrwxrwx
while 755 = rwxr-xr-x
The first three columns rwx-permissions owned by the owner stating the file / directory.
three-column-two states rwx permissions owned by a group of ownernya. Owners have a user group ..
-three-column “rwx” third states which are owned by other permissions, meaning here other than the owner and group.