JavaScript Function declaration vs expression

Function declaration:

1. appear in the global scope
2. appear inside a function

Features: Hoisting
Available: Anywhere inside scope (global and local)

Function expression:

1. can be assigned to a variable
2. can be assigned to a property
3. can appear in function invocations as parameters

Features: Closures, Callbacks, IIFE (Immediately Invoked Function Expressions)
Available: after the line it is declared