logical operators

“Programs must be written for people to read, and only incidentally for machines to execute.”

Harold AbelsonStructure and Interpretation of Computer Programs

Logical operators are generally symbols or words which connect two or more expressions that allow a program to make a decision based on a given set of conditions.

Logical operators usually control the program flow and are frequently used with the if, while, or some other control statement.

Three (3) Types Logical Operators

  1. Logical AND operator (&&): For logical AND operators, both conditions must be true for the statement to be true. If one of them is false, then the program will return false.
let a, b;
a = 3; b = 4;
console.log(a === 3 && b === 4) //TRUE
console.log(a === 3 && b === 3) //FALSE

2. Logical OR operator ( || ): For logical OR operators, one of the operands just have to be true for the statement to be true.

//Using variables from our first example
console.log(a === 3) || (b === 4) //TRUE
console.log(a === 3) || (b === 3) //TRUE

3. Logical NOT operator ( ! ): This is used to reverse the logical state of its operands. If a condition is true, then the Logical Not will make it false.

//Using variables from our previous example
console.log(!(a === 3)) //FALSE

Leave a Reply

Your email address will not be published. Required fields are marked *