Purpose of singletons in programming

Question

This is admittedly a rather loose question. My current understanding of singletons is that they are a class that you set up in such a way that only one instance is ever crea

Answer 1

1. Singleton is a very useful replacement of global variables, used all across the code.
   
2. Singletons are usually not "new"ed or "delete"d, they tend to be initialized on first use and deleted along with program scope
   
3. Singletons perfectly match for wrapping logging, configuration and other hardware-interfacing classes.