This chapter illustrates how object literals may be considered singleton objects. It also explains how to create singleton objects using the immediate‐execution modules. The object literal is the simplest implementation of the Singleton Pattern in JavaScript. The current implementation of the returnValueCache already uses an object literal as a cache, so injecting an optional object literal as the shared cache is the easiest way to add the desired functionality. While the object literal is literally the simplest implementation of the Singleton Pattern, it lacks the ability to hide data and other desirable qualities that are provided by other object creation patterns, such as the Module Pattern. Implementations of the Singleton Pattern in JavaScript, such as object literals and immediate‐execution modules, are easier to make reliable than in other languages because JavaScript is single‐threaded.