What is the difference between block scope and function scope in JavaScript?

What is the difference between block scope and function scope in JavaScript?

In JavaScript, function scope means that variables are only accessible within the function they are declared in. Block scope, introduced with ES6, allows variables to be limited to the block (enclosed by curly braces) they are defined in.

Can you give me an example of each?

Sure! For function scope, if you declare a variable inside a function, it won't be accessible outside of it. For block scope, if you declare a variable with let or const inside an if statement, it won't be accessible outside that if block.

What happens if I use var inside a block?

Using var inside a block will still make the variable function-scoped, meaning it will be accessible outside the block but within the function.

Why should I prefer block scope over function scope?

Block scope helps prevent variable hoisting issues and reduces the risk of variable collisions, making your code cleaner and easier to maintain.