In this lesson, you'll learn about the basic syntax and functionality of logical operators in JavaScript, which are used to combine multiple conditions.

Logical Operators Part 1

Logical operators are used to combine two or more conditions. JavaScript includes three logical operators: (OR), (AND), and (NOT).

Complete knowledge of logical operators requires an understanding of if/else statements and truthy and falsy values. In this lesson, we'll cover the syntax of logical operators, and we'll revisit them in more detail after covering those topics.

AND Operator

The double ampersand is known as the AND operator. It checks whether all operands are truthy values. If they are, it returns ; otherwise, it returns .

// **AND Operator (&&)**
console.log(true && false); // false
console.log(true && true);  // true
console.log(false && false); // false

You can also pass multiple conditions:

console.log(true && true && false); // false

OR Operator

The double vertical bar is known as the OR operator. It checks whether at least one operand is a truthy value. If there is at least one truthy value, it returns ; otherwise, it returns .

// OR Operator (||)
// The double vertical bar **||** is known as the OR operator. It checks whether **at least one operand** is a truthy value. If there is at least one truthy value, it returns **true**; otherwise, it returns **false**.
console.log(true || false); // true
console.log(true || true);  // true
console.log(false || false); // false

You can also pass multiple conditions:

console.log(true || true || false); // true

NOT Operator

The exclamation mark is known as the NOT operator. It reverses the boolean result of a condition.

The syntax is straightforward:

**// NOT Operator (!)**
// The exclamation mark **!** is known as the NOT operator. It reverses the boolean result of a condition.
console.log(!true);  // false
console.log(!false); // true

As you can see, the NOT operator simply converts boolean to , and boolean to .

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