The Arpanet and computer networks

In 1964 only large mainframe computers existed, each with its own separate set of users. If you were lucky the computer was timeshared, but even then you could not go far away since the terminals were hardwired to it or connected by local phone line. Moreover, if you wanted data from another computer you moved it by tape and you could forget wanting software from a different type of computer. Thus, most users were tied by their computer and terminal to a very restricted enviornment.