logical.md

Overview

We'll discuss the three logical operators in JavaScript, which are detailed in the table below. These are the not (!), and (&&), and or (||) operators. These are commonly used when working with Boolean values.

To better understand how these operators work, let's dive in to some exercises instead.

Exercises

1. Declare a variable called isRed and set its value to true.
2. Log to the console the result of !isRed. ! is the not operator.
3. Log to the console the result of !!isRed. Negating a negation just brings back the original value!
4. Declare a variable called isRound and set its value to false.
5. Log to the console the result of isRed && isRound. Here we're trying to check if something is both red AND round.
6. Log to the console the result of isRed || isRound. In this example, we're trying to see if something is either color red or is round in shape (or both!).
7. Change the value of isRound to true and try doing exercises 5 & 6 again. What changed in the output? Does it make sense with the description of the logical operators?
8. Try logging to the console the result of true && true && true. This shows us we can keep extending the expression. You can even try out false || false || false || false and keep going on and on...
9. Finally, try combining all three and use parentheses () to group statements together if it gets too complicated. !true && (false || true) && !false