Stemming from a National Science Foundation project, Logo was created by Seymour Papert in the mid-1960s along with colleagues at MIT and members of Bolt Beranek & Newman. Originally developed on large computers, it was later adapted to many personal computers. A wealth of information about Logo and its educational philosophy is available from the Logo Foundation, http://el.media.mit.edu/Logo-foundation.
Command the Turtle
Turtle Graphics is the graphics language built into Logo, which allows complex graphics images to be created with a minimum of coding. The turtle is a triangular-shaped cursor, which is moved on screen with commands that activate the turtle as if you were driving it, for example, go forward 100 units, turn right 45 degrees, turn left 20 degrees.
The following Object Logo example converts Fahrenheit to Celsius:
convert local [fahr] print "|Enter Fahrenheit | make "fahr ReadWord print "|Celsius is | print (:fahr - 32) * 5 / 9 end
The Logo Turtle
Logo's Turtle Graphics provides a simple, intuitive way to learn about and program graphics. The commands cause the triangular pointer (the turtle) to draw the image on screen.
![]() | Reproduced with permission from Computer Desktop Encyclopedia. Copyright (c) 1981-2009 The Computer Language Company Inc. All rights reserved. |
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