Some cryptocurrencies recently saw their biggest drop in years. Author: Alexis Rodriguez Updated: 9:45 AM PDT May 25, 2021 SEATTLE — Digital currencies are a form of payment. You can use them in exchange for goods and services. Cryptocurrencies work using a technology called "Blockchain." It's essentially a very secure and permanent leger of all cryptocurrency transactions. It's able to connect computers from all around the world. Some of the more common cryptocurrencies are Bitcoin, Ethereum and Dogecoin. These digital currencies have skyrocketed in popularity over the past few years. However, in just the last week, something big happened in the crypto world. All the markets experienced a massive drop. For some cryptocurrencies, it was the biggest drop they'd seen in years.