What is hoisting in JavaScript?

Hoisting in JavaScript is a fundamental concept that reveals how JavaScript interprets and executes code. Simply put, hoisting means that variable and function declarations are 'moved' to the top of their execution context before the code is actually executed. This enables us to use variables and functions before they have been declared in the code. However, it is vital to understand that only the declarations are hoisted; their assignments occur in the places they are written in the code. Therefore, if you try to access a variable before its declaration, it will likely return 'undefined'. Regarding functions, hoisting operates similarly, which is why we can invoke functions before their declaration in the code. Developers need to be cautious when utilizing hoisting to avoid misunderstandings, debugging difficulties, and to organize the code effectively for better readability and maintainability. It is worth noting that hoisting does not behave the same way for variables declared with 'let' and 'const', which calls for extra attention from the programmer.