24 Jan 2020 In this article, we look at how to declare variables in an easy-to-read way. Also, we look at ways to avoid declaring global variables and hiding 


assign to declared variable timer = setTimeout(function(){alert('Time's up'); }, totalTime); } function clear(){ console.log('stopped') clearTimeout(timer); } 

We use let because it allows us to declare block scoped variables, which means that if it’s declared in a function or class, then it cannot be changed outside of there. To use let to declare a variable, we put: let a = 1; The equal sign is the assignment operator. In JavaScript, it's possible to declare variables in a single statement. let x = 5, y = 6, z = 7; If you use a variable without initializing it, it will have an undefined value. Variables are a fundamental concept in any programming language. In JavaScript, you can declare variables by using the keywords var, const, or let. In this article, you’ll learn why we use variables, how to use them, and the differences between const, let and var.

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} // Declare