What is Hoisting in JavaScript?
Hoisting is a behavior where the JS engine moves variable and function declarations to the top of their containing scope before the code actually runs.
How it works:
• During the creation phase, JS scans the code and allocates memory for declarations.
• var: The declaration is moved up and initialized as undefined.
• let & const: These are hoisted but stay uninitialized in a "Temporal Dead Zone." Accessing them before declaration causes an error.
• Functions: Full function declarations are moved to the top, including their entire body.
Problem it solves:
It removes the strict need to define functions before calling them. This allows you to place main logic at the top of a file and helper functions at the bottom, making the code easier to read.
July 19, 2026 198
