What is the purpose of the let keyword in javascript #coding #js #shorts

What is the purpose of the let keyword in javascript #coding #js #shorts
Q.17 What is the purpose of the let keyword

The let keyword in JavaScript is used to declare block-scoped variables, meaning the variable declared with let is only accessible within the block (or statement) in which it is defined. This contrasts with var, which is function-scoped, meaning it is accessible within the entire function in which it is declared, or globally if declared outside any function.

Key Characteristics of let:
1. Block Scope: Variables declared with let are limited to the block (or statement) in which they are defined. A block is typically defined by curly braces {} (like in if, for, or while blocks).
2. No Hoisting: While variables declared with var are hoisted (i.e., moved to the top of their scope), variables declared with let are not hoisted. They are in a "temporal dead zone" from the start of the block until the declaration is encountered, which means you can't access the variable before it's declared.
3. Re-declaration Not Allowed in the Same Scope: Unlike var, you cannot redeclare a variable within the same block or scope using let. This helps prevent accidental variable redeclarations.
4. Supports Re-assignment: You can reassign a value to a let variable after it has been initialized.

Example of let:
{
let a = 10;
console.log(a); // Outputs: 10
}

console.log(a); // Error: a is not defined because a is block-scoped
In the example above, a is only accessible within the block where it is defined. Outside the block, it’s undefined.
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