What is the difference between var, let, and const?

var, let, and const are used to declare variables in JavaScript, but they differ in scope and mutability. var is function-scoped and can be redeclared and reassigned, whereas let and const are block-scoped. let allows reassignment, const cannot be redeclared or reassigned.

What is the spread operator (...)?

The spread operator (...) is used to expand arrays or objects. It allows merging multiple arrays or objects, creating shallow copies that can be modified without affecting the original.

What is the difference between map(), filter(), and forEach()?

map(), filter(), and forEach() are array iteration methods with different purposes. map() transforms each element and returns a new array, filter() selects elements that meet a condition and returns a new array, while forEach() executes a function on each element but does not return anything.

What is an arrow function?

An arrow function is a concise way to write functions in JavaScript. It has a shorter syntax compared to traditional function expressions.

What are template literals?

Template literals are string literals enclosed in backticks (`) that allow multi-line strings and embedding expressions using ${}.