Parse.com provides a backend service to developers. If your mobile or desktop app requires a backend on the internet, then Parse is one of the options you can choose.
I first came across the service a few months ago and noted that they provide SDKs that let your apps running on various devices connect up to the backend it provides. They provide SDKs for devices running iOS, Android, Windows (Phone) 8, OS X and Javascript.
Today, I want to take a closer look to see what you get, how much it costs and if it potentially replace your own provisioned services and code that you use to interface with your own servers.