Of course pinging a single known IP address is the most simple task in networking but there arises a need when you need to know which devices and systems are available on your network.
For that purpose, the following simple command can do the job for you in Linux:
for ip in $(seq 1 254); do ping -c 1 192.168.1.$ip>/dev/null; [ $? -eq 0 ] && echo "192.168.1.$ip UP" || : ; done
It will start pinging all the addresses from 1 to 254 in the provided network. Change 192.168.1. to whatever you want.