Bitcoin hit a new all-time high of over $67,000 in November 2021.

El Salvador became the first country to adopt Bitcoin as legal tender in September 2021, with other countries considering similar moves.

Non-fungible tokens (NFTs) have exploded in popularity, with high-profile sales of digital art and other collectibles fetching millions of dollars.

Ethereum, the second-largest cryptocurrency by market capitalization, has been undergoing a major upgrade known as Ethereum 2.0, which aims to improve the network's scalability and security.