Our early versions of ZOG, created in 1976, ran on DEC time-sharing machines with 1200 baud terminal links and provided response times of 5 to 10 seconds. When we graduated to 9600 baud around 1979, response was improved to about 2 or 3 seconds, and it seemed like a major breakthrough to users.
Google-1
Google-2
»ThesaHelp: Copyright 1988 by the ACM