Incompatible Timesharing System - User Environment

User Environment

The environment seen by ITS users was philosophically significantly different from that provided by most operating systems at the time.

• Initially there were no passwords, and a user could work on ITS without even logging on. Logging on was considered polite, though, so people knew when you were connected.
• To deal with a rash of incidents where users sought out flaws in the system in order to crash it, a novel approach was taken. A command was implemented which anyone could run which caused the system to crash, which took away all the fun and challenge of doing so. It did, however, broadcast a message to say who was doing it.
• All files were editable by all users.
• All users could talk with instant messaging on another's terminal, or they could use a command (SHOUT) to ask all active users for help.
• Users could see what was happening on another's terminal (using a command called OS for "output spy"). A target of OS could detect and kill it using another command called JEDGAR, named for FBI Director J. Edgar Hoover). This facility was later disabled in an interesting way: it looked like the session was killed, but was not.
• Tourists - guest users either at MIT AI Lab terminals, or over the ARPAnet - were permitted. A policy was later published on tourist access. The local spelling "TURIST" is an artifact of six character filename (and other identifier) limitations, which is traceable to the fact that six SIXBIT encoded characters fit in a single 36-bit PDP-10 word. "TURIST" may also have been a pun on Alan Turing.