In the two lessons (here and here) you learned how to generate true or false answers based on the comparison between numbers. The questions were simple, always asking a single question. What about more complex (or compound) questions? What do we mean?

When you search for a book at the library, you can do a search by subject, say "programming." This might take the form of a line like "subject=programming." If you wanted to narrow your search to look for books about programming by the author "Wirth" then you might submit a compound question like "subject=programming" and "author=wirth." Notice the use of the word "and." Say you wanted books either on programming or Australia. You might do a search like "subject=programming" or "subject=Australia." Notice the use of the word "or." True/false questions in computer programming can also involve the words "and" and "or," and they'd mean just what you'd think.

And and or are logical operators and sit between two single (simple) questions. Both of these take the answers to the individual questions to the left and right of them and combine their answers into another single true or false answer.

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Here is some code that will choose a random number from -100 to 100 and put it into variable a. Let's do some tests on variable a using and's and or's.