Many years ago, when I was still a schoolboy, I opted to take “Computer Science” as an optional extra subject. I failed and dropped out halfway through the first year. I remember very little, other than that I did not like the teacher, I had no clue what the word “variable” meant – and the LOGO Basic turtle.
Create a free account to save your programs and head on over to the Lessons page for more!

I was well pleased to see that the little turtle lives online now; hop on over to the Turtle Academy Playground on the following link: https://turtleacademy.com/playground and give the guy a little spin!
Enter (or copy) the following set of instructions into the code window (the input with the placeholder text Type your code here…) and then click on the Run button:
fd 100 rt 90 fd 100 rt 90 fd 100 rt 90 fd 100 rt 90
The above “code” features in the post Pseudo-code: teaching programming
Read all about the history of the LOGO language on Wikipedia: Logo_(programming_language)