Nuprl
is designed to run on a terminal with an
ordinary
keyboard with a control key, a keypad with nine
keys arranged as in figure 
and, optionally, a mouse.
In the subsequent discussion we shall assume that these are available, and
we shall assume that the
mouse comes with three
buttons called L, M and
R (for left, middle and right, respectively) and is activated by
clicking one of these buttons.
However, one may simulate moving the mouse by using the keypad as follows.
The arrow keys are used to move the cursor; if
the arrow keys are used alone then the cursor moves in the direction of the
arrow by either a single character or a single line. The cursor can be made
to move in larger steps by pressing the key LONG
LONG
} before
the arrow
key.
The COMMAND
COMMAND
} key
is used for returning to the command window
momentarily while in the middle of editing.
For any particular terminal one may have to simulate the keypad and/or
the mouse on the keyboard using control keys in
combination with ordinary keys.
DIAG
}
}JUMP
}
}LONG
}
}SEL
}
}MOUSE
}
The mouse is used for moving the cursor on the screen, for opening windows and for moving windows. An arrow on the screen called the mouse cursor responds directly to movements of the mouse. We shall also have occasion to refer to the cursor which responds to the keyboard and keypad commands as the cursor . To move the cursor, one places the mouse cursor at the desired position and clicks button R.
