Changes

Both of the above commands will work. However, the first one gives execute permission to user, groups and other (in otherwords '''everyone'''). This is not the most secure way of allowing your scripts to be executed. The second one is a much better practice, which will give only your user execute permission.

=== $PWD and pwd, what is the difference? ===

=== Exit codes and $? ===

$? is a special variable that contains the exit code of the last executed command. Linux uses an exit code of 0 to represent success. Any non-zero value represents failure. To check the exit status of the last command use '''echo $?'''.

* How to create a variable and set a value in it