Can only have a value of true or false
true/false are special keywords in JavaScript and do not have quotes around them
// declare a variable called isOn and assign a value of true
const isOn = true
// declare a variable called isWarm
let isWarm
// assign a value of false to isWarm
isWarm = false
Booleans are useful for helping our programs make decisions (when used with conditionals, comparison & logical operators)
Booleans also helps a program known when it should stop/start looping