Instruction manual

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Logo is a programming language that can be used to teach your PC to do some
new things. One thing Logo can teach your PC is how to draw pictures. This
system of drawing is called Turtle Graphics. To view the built-in samples divided
into Logo Beginner, Logo Intermediate & Logo Advanced, click Example icon.
Commands
Instructions to the Turtle are called commands. Each command begins with a key
word telling the Turtle what to do. For example, “forward” is a command that
tells the Turtle to move forward; “right” is a command that tells the Turtle to
turn to the right. Often, commands will require additional information. For
example, how far forward the Turtle should go. For example, “forward 10” tells
the Turtle to move forward 10 Turtle steps; “right 90” is a command that tells
the Turtle to turn 90 degrees (a quarter turn) to the right. If additional information
is required for a command, it must appear immediately after the command,
separated from the command by a space.
In the home position, the Turtle, represented by a triangle, sits at the center of
the screen pointing straight up. This location is indicated with the pair of numbers
(0,0). The first number of this pair indicates how far left or right the Turtle is
from the center of the screen; it is also called the x-coordinate. The second number
indicates how far up or down the Turtle is from the center of the screen; it is also
called the y-coordinate. For example, the pair (10, -5) indicates that the Turtle is
10 steps to the right and 5 steps below the center of the screen.
Routines
Additional commands can be created by defining new Logo routines. For example,
here is a Logo routine to tell your PC how to make a square:
The title “to square” – should be indented way as well as the final line “end”.
The command lines should be single-spaced. Also if possible we would like all
the examples to appear in fixed pitch font Example:
to square
forward 10
right 90
forward 10
right 90
forward 10
right 90
forward 10
right 90
end