An immediately-invoked function expression (or IIFE, pronounced "iffy") is a JavaScript programming language idiom which produces a lexical scope using JavaScript's function scoping. Immediately-invoked function expressions can be used to avoid variable hoisting from within blocks, protect against polluting the global environment and simultaneously allow public access to methods while retaining privacy for variables defined within the function. This concept has been referred to as a self-executing anonymous function, but Ben Alman introduced the term IIFE as a more semantically accurate term for the idiom, shortly after its discussion arose on comp.lang.javascript.