Bitcoin hit a record high of nearly $18,000 per coin on Friday, December 15.

Two years ago, the idea of buying the virtual currency even at that price was laughable. After a rapid rise in value in 2013, the cryptocurrency's value more than halved by mid-2015.

At its lowest point, one bitcoin was equal to about $230.

Given the currency's covert nature, the average person still may not understand how buying and selling actually works.

Using the app Coinbase, which lets anyone trade bitcoins for a small fee, we decided to find out.

A brief warning: If you're going to do this, tell your bank you're about to buy bitcoin. More on that later.

And to read more about blockchain, the technology powering bitcoin, click here.