What does '>/dev/null 2>&1' mean
> is for redirect
/dev/null is a black hole where any data sent, will be discarded
2 is the file descriptor for Standard Error
> is for redirect
& is the symbol for file descriptor (without it, the following 1 would be considered a filename)
1 is the file descriptor for Standard Out
Therefore >/dev/null 2>&1 is redirect the output of your program to /dev/null. Include both the Standard Error and Standard Out.
Much more information is available at The Linux Documentation Project's I/O Redirection page.