Use the assignment operator = to assign a value to a variable:

const a = 2
let b = 2
var c = 2

This operator has several shortcuts for all the arithmetic operators which let you assign to the first operand the result of the operations with the second operand.

They are:

• +=: addition assignment
• -=: subtraction assignment
• *=: multiplication assignment
• /=: division assignment
• %=: remainder assignment
• **=: exponentiation assignment

Examples:

let a = 0
a += 5 //a === 5
a -= 2 //a === 3
a *= 2 //a === 6
a /= 2 //a === 3
a %= 2 //a === 1

To be clear, the above operations are executed one after another, so a at the end is 1, not 0