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JavaScript JavaScript Basics Making Decisions in Your Code with Conditional Statements Boolean Values

why using "let" in javaScript

teacher use "let" in this course. why I need to use "let" here ?

what is the different if let , var

2 Answers

Steven Parker
Steven Parker
210,475 Points

For simple things you can use either one, the main differences have to do with concepts like scope and hoisting.

For more details, see the MDN pages on let and var.

Ainne Oum
Ainne Oum
3,221 Points

Hi Leo, Always use const... if you must have a variable that will need to change, then use let. In most cases you will only see var when learning about JS. It's important to use let or const to prevent hoisting in our functions... which can cause bugs... It is good practice to always use const first.