How does hoisting affect function declarations in JavaScript?

Function declarations in JavaScript are hoisted to the top of their containing scope, which can be either a function scope or the global scope, depending on where the function is declared. This means that the entire function definition, not just its name, is made available throughout the entire scope, allowing you to invoke the function even before it appears in the code.

For example, if you have a function declared, you can call it before its actual declaration in the code without resulting in an error. This behavior is due to hoisting, where the JavaScript engine moves the declarations to the top during the compilation phase.

It's important to note that while variable declarations (using var) are also hoisted, function expressions, especially those declared using const or let, are subject to different hoisting rules and only exist after their definition. This distinction highlights how function declarations are treated differently within JavaScript's hoisting behavior compared to other types of declarations.