Definition of the word log on

The term "log on" originally referred to the process of physically inserting a wooden log into a computer's input device, known as a teletype terminal, to communicate with other devices or systems in the early days of computer networking in the 1960s. This input device was named a teletype because it resembled the typewriters used for telegraph communications, which had a paper roll or "tape" to record input and output. The term "log" (short for "loggerhead") referred to a device that inserted and removed the tape from the machine's reader and punch mechanisms. Eventually, as computer technology evolved and teleprinters were replaced by common computer keyboards, the literal meaning of the term "log on" also changed. "Logging on" came to mean the process of entering a user's ID and password into a computer or network system to establish a connection and access resources. The words "login" and "logout", which share common etymological roots with "log on" and "log off", are still widely used to describe the process of connecting to and disconnecting from a computer or network system, respectively.