What is the fundamental difference between storing the function in a variable in these two ways?

Question

This is really basic javascript here and probably pretty silly to ask but what is the difference between:

a) function variable(){}; b) var variable = function() {};

I think the second one executes as soon as the browser reads it, am I correct?

Answer 1

Your first example is a function statement. The second is a function expression. Per MDN:

The main difference between a function expression and a function statement is the function name, which can be omitted in function expressions to create anonymous functions. A function expression can be used as a IIFE (Immediately Invoked Function Expression) which runs as soon as it is defined. See also the chapter about functions for more information.