'"UCLA36" seems a particularly bad choice; "UCLA91" would be much better.'
In September 1971, Peggy Karp of MITRE in McLean — a mere five miles (8 km) from Washington, DC — had suggested agreeing on easy to remember names for the machines by then accessible on ARPANET (the young Internet). For the machine at University of California, Los Angeles, with address 65, she suggested UCLA36.
UCLA's Bob Braden replied immediately. As we've read, he preferred UCLA91 for machine 65.
Why 36 or 91? As far as I can tell, the computer at that address was a versatile and powerful IBM System/360 — Model 91.
Address 65 became known as UCLA-91 and Peggy Karp's list became today's system of domain names — which, of course, make up an essential part of an email:
›› Find out what parts make up an email address — and which characters are okay to use in it.