We can add additional layers of logic in our conditional statements using logical operators.

There are three logical operators:

• The and operator (&&)
• The or operator (||)
• The not operator, otherwise known as the bang (!) operator

The and operator

When we use the && operator, we are checking that two things are true.

let age = 18
let drunk = false

if (age >= 18 && !drunk) {
  console.log("You can drive.")
} else {
  console.log("You can not drive.")
}

When using the && operator, both conditions must evaluate to true for the entire condition to evaluate to true and execute.

The or operator

If we only care about either condition being true, we can use the || operator.

let day = "Saturday"

if (day === "Saturday" || day === "Sunday") {
  console.log("Time to party!")
} else {
  console.log("Time to work!")
}

// Time to party!

When using the || operator, only one of the conditions must evaluate to true for the overall statement to evaluate to true.

The bang operator

The ! operator reverses or negates, the value of a boolean.

let drunk = true

console.log(!drunk) // Prints false

let tipsy = false
console.log(!tipsy) // Prints true

Essentially, the ! operator will either take a true value and pass back false, or it will take a false value and pass back true.