Arithmetic Operators

Just like in Basic Maths, we can do Mathematical operations in a programming language. Think of addition, subtraction, division (without the long), multiplication, exponentiation, and modulus.

Addition +

Represented by the plus symbol. It is used to add two operands together.

Example:

let total = 20 + 30;

In JavaScript, you can add numbers to strings - but it behaves in a weird way. See the example below:

let x = 10;
let y = 20;
let name = "Sankara";
 
let sum = x + y + name; // Will return 30Sankara
let sum2 = name + x + y; // Will return Sankara1020

The value of sum will be 30Sankara because the first value encountered is an integer, then another integer, then a string value. Therefore, the integers will be added and then the string will be appended to the end of the sum because strings are not integers.

In the second case however, because the string value is the one that begins, then the entire expression is treated as a string. So, even x and y in the second expression are considered strings. Therefore, the values are concatenated and not added. Read more about String Concatenation.

Subtraction -

Represented by the minus symbol. It used to get the difference between two operands.

Example:

let difference = 20 - 30; // Just like in Maths, numbers can be in the negative.

Multiplication *

Represented by the asterisk. Since computers understand the letter X as the letter X, we cannot use it for multiplication like we do when writing. So, we use the asterisk symbol to multiply operands.

Example:

let product = 20 * 30;

Division /

Represented by the forward slash. This is used to get the quotient between two operands.

Example:

let quotient = 20 / 4;

Modulus %

Represented by the percent symbol. It is used to get the remainder of a division.

Example:

let modulus = 19 % 4; // Returns 3

When you use modulus, the value you get back will be the remainder after division is done.

Exponentiation **

Represented by double asterisks. It is used to get the power - to a certain value - of an operand.

Example:

let product2 = 20 ** 2; // 20 raised to the power of 2
let product3 = 20 ** 3; // 20 raised to the power of 3
let product4 = 20 ** 4; // 20 raised to the power of 4

Operator precedence

Operator precedence means the order of execution of operations depending on the Mathematical Symbol used, i.e BODMAS.

BODMAS stands for Brackets, Order of powers (also called Of), Division, Multiplicataion, Addition, and Subtraction, and it behaves the same way in programming as it does in Mathametics:

Operands in brackets are executed first, then the order of powers, then divided, then multiplied, added and finally subtracted. Take a look at the example below:

let total = (40 - 20) / 3 * 10; // Returns 66.66 recurring

In the above example, we first get the value of 40 - 20 because they are in brackets, then we divide this new value by 3, and then finally multiply it by 10. Try to solve the examples below:

let total = 10 * 10 + 10;
let profit = 10 / 10 * 10;
let grossProfit = (2400 - 1500) / 12 * 100;

That is going to be it about Arithmetic Operators. Next, we are going to look at Logical Operators.