What kind of scope does the `let` keyword provide for variables?

What kind of scope does the `let` keyword provide for variables?

• A. Global scope
• B. Function scope
• C. Block scope
• D. Module scope

Answer: (C)

The `let` keyword in JavaScript provides block scope for variables. This means that any variable declared with `let` is limited in scope to the block in which it is defined. A block is defined by curly braces `{}`, such as in conditional statements (`if`, `else`), loops (`for`, `while`), or any other structure that creates a block. For example, when a variable is declared using `let` within a `for` loop, it is only accessible within that loop, and not outside of it. This is different from variables declared with `var`, which has function scope, meaning they are accessible throughout the entire function in which they are declared, regardless of block boundaries. Block scope helps prevent issues such as variable collision or unintended access, providing better control over variable visibility and lifetimes. In summary, using `let` ensures that variables are block-scoped, enhancing encapsulation and reducing errors related to variable reuse across different scopes in your code.

The let keyword in JavaScript provides block scope for variables. This means that any variable declared with let is limited in scope to the block in which it is defined. A block is defined by curly braces {}, such as in conditional statements (if, else), loops (for, while), or any other structure that creates a block.

For example, when a variable is declared using let within a for loop, it is only accessible within that loop, and not outside of it. This is different from variables declared with var, which has function scope, meaning they are accessible throughout the entire function in which they are declared, regardless of block boundaries. Block scope helps prevent issues such as variable collision or unintended access, providing better control over variable visibility and lifetimes.

In summary, using let ensures that variables are block-scoped, enhancing encapsulation and reducing errors related to variable reuse across different scopes in your code.