How To Find a WordPress Post ID

Help! What is my WordPress Post ID?

Older versions of WordPress used to display the Post ID in the Dashboard. Since then, this feature is no longer available. Why? I have no idea. But fortunately there are a couple of alternate ways to find the Post ID. For the average user of WordPress this number is usually needed for a specific function. For example, there are some themes that have a Featured Slider that requires this number in order to work.