Pagers were these magical devices with a 7 digit (10 if you include area code) number attached to them. You paid a monthly rate and people could then call the number and the pager would beep to let you know someone was looking for you. then you would go and find some quarters, find a payphone and call the number back that appeared on your screen. Its a little bit more complex than that, but that's the gist of it.
Back in the days of pagers RIM sold a two way pager. The device could send and recieve alphanumeric pages, this was huge when most pagers were only numerical. This pager was as thick as two phones had a physical keyboard and a very low resolution screen. A friend had one and he was the envy of all!
