B$.$ Chmod changes the file mode of each specified either

symbolic representation

an octal number representing

C$.$ Octal representation

U: user

G:group

O:Owner

Example: chmod $754$ file$1$

$.4$ stands for "read",

$.2$ stands for "write",

$.1$ stands for "execute", and

$.0$ stands for $"$no permission."

chmod $754$ file $1$

$U=7(4+2+1)($read$,$ write and execute$).($rwx$)$

$G=5(4+0+1)($read and execute$).(r-x)$

$O=4(4+0+0)($read only$).($r$--)$

So$,$ meaning is $($ rwxr$-$xr$--)$

Question: Find Set permission for the following commands:

chmod $644$ file.htm

chmod $666$ file.txt

D$.$ symbolic representation

The format of a symbolic mode is:

$[$ugoa$...][[+-=][$perms$...]...]$

& $[$ugoa$]$:

$U$ : the user who owns it$.$

$$ g: chmod options permissions

$$ o: onner usersingednetne tres group

$$ a: all users