The /dev/null is a character file. I like to compare the /dev/null file with a worm hole, because it eats data.

$ file /dev/null
/dev/null: character special
The data redirected to the /dev/null is discarded by the system.
When debugging shell scripts, a good practice is to redirect the standard output to /dev/null, to avoid the error statement and look only at the error.
Next I will show you how to redirect to /dev/null. Also, read this article if you are interested in output redirection.
Redirect the standard output to /dev/null:
$ ./script > /dev/null
Redirect the standard error to /dev/null:
$ ./script 2> /dev/null
Redirect both standard output and standard error to /dev/null:
$ ./script &> /dev/null
OR:
$ ./script > /dev/null 2>&1