http://el.www.media.mit.edu/groups/logo-foundation/logo/index.html

To learn more about Logo, visit the URL listed above. Logo was the original "Turtle Graphics". It was designed to be a simple beginning programming language that interacted with the learner. The turtle graphics tutorial and the scripting language detailed in this newsletter both derive from Logo.

Below are some interesting quotes from the website. It is definitely worth a visit to learn more.

INTERACTIVITY
Although there are some versions of Logo that compile, it is generally implemented as an interpreted language. The interactivity of this approach provides the user with immediate feedback on individual instructions, thus aiding in the debugging and learning process. Error messages are descriptive.

THE TURTLE:
The most popular Logo environment has involved the Turtle, originally a robotic creature that moved around on the floor.

It can be directed by typing commands at the computer. The command forward 100 causes the turtle to move forward in a straight line 100 "turtle steps". Right 45 rotates the turtle 45 degrees clockwise while leaving it in the same place on the floor. Then forward 50 causes it to go forward 50 steps in the new direction.

With just the two commands forward and right, the turtle can be moved in any path across the floor. The turtle also had a pen which may be lowered to the floor so that a trace is left of where it has traveled. With the pen down, the turtle can draw geometric shapes, and pictures, and designs of all sorts.

Off the Floor and Onto the Screen

The turtle migrated to the computer screen where it lives as a graphics object. Viewing the screen is like looking down on the mechanical turtle from above.

The screen turtle also understands forward and right. (read more at the website!)