Declaring a variable means creating a variable and giving it a name so that JavaScript can store data in it.
In JavaScript, variables are declared using special keywords. These keywords tell the browser how the variable should behave in the program.
Learning the correct way to declare variables is very important because it helps you write safe, clear, and professional code.
Ways to Declare Variables in JavaScript
JavaScript provides three main keywords for declaring variables:
- var – old way, used in older code
- let – modern way, used for values that can change
- const – used for values that should not change
Understanding the difference between these helps you choose the right method.
The var keyword was used in older JavaScript versions. It works, but it has some problems with scope, which can cause unexpected behavior in large programs.
Today, most developers prefer let and const instead of var.
The let keyword is used when the value of a variable may change later in the program.
In this example, the value of age is updated, which shows that let allows reassignment.
The const keyword is used when a value should remain the same throughout the program.
Choosing the right way to declare variables makes your code safer, easier to understand, and more professional.