Yeah back on the days of analogue telephone lines every phone number ultimately required 2 copper wires going all the way from the nearest local exchange to the telephone handset in the home or business, so many smaller towns and rural areas got party lines as a way to save on copper and switching costs. Instead of a dedicated pair of copper wires to every house with a phone, all of the houses on a given block were on one line (all on one electrical circuit), so you'd pick up the phone and be able to talk to (or listen to) your other neighbors without dialing.

Edit to add: in some rural areas they'd even use the barbed wire fences already at farms as a wire for delivering telephone service instead of running new phone lines, sometimes even using Single Wire Earth Return to further reduce copper requirements

The Kinks even wrote a song about it

My server wouldn't let you on with mIRC unless you were at least cool enough to disguise it/use a bouncer. Kept the M$ riffraff out ;)