NFT sales hit $555 million over the past week. These were the 5 best-selling digital collections.

• NFT sales had a breakthrough year in 2021, with total sales volume surging to $14 billion.
• The NFT market is dominated by a handful of standout leaders due to their popularity and rarity.
• These are the five best-selling digital collectibles that helped drive $555 million in NFT sales over the past week.
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The cryptocurrency boom over the past few years has helped propel a newer market to record heights: digital collectibles known as NFTs.

In fact, 2021 was a breakthrough year for NFTs, with total sales volume topping $14 billion as artists, investors, and entrepreneurs descend upon the nascent Web3 space.

NFTs, or non-fungible tokens, are unique, irreplaceable, mostly digital items that users buy and sell online.

NFTs use blockchain technology to keep a digital record of ownership, similar to cryptocurrencies. They were first launched on ethereum, the same blockchain that supports the cryptocurrency ether, and most NFTs can still only be purchased using ether.

In the past week alone, sales of NFTs hit $555 million, according to data from NonFungible.com.

With NFT sales soaring, these are the five best-selling NFT collections over the past week, according to NonFungible.

5. FLUF World

7-Day Sales Volume: $13.2 million
Number of Sales: 930
Highest Sale Price: $184,709

Explainer:"FLUFs have been programmatically generated from 270 attributes across 14 categories to be entirely unique by at least three degrees of separation. This also excludes their expression, dance, scene, and soundtrack. FLUFs are stored as ERC721 tokens on the Ethereum blockchain."

4. CyberKongz

7-Day Sales Volume: $14.2 million
Number of Sales: 1,221
Highest Sale Price: $295,298

Explainer: "CyberKongz are unique and randomly generated 2D/3D NFT Social Avatars for your online experiences. Some appear normal. Some look weird. Some are just damn cool! Maybe some even look familiar!"

3. The Sandbox

7-Day Sales Volume: $24.2 million
Number of Sales: 1,632
Highest Sale Price: $84,553

Explainer: "The Sandbox is a community-driven UGC-voxel platform where users own their LAND and host their creative magic."

2. CryptoSkulls

7-Day Sales Volume: $33.5 million
Number of Sales: 5,744
Highest Sale Price: $332,275

Explainer: "CryptoSkulls are 10,000 collectible ERC-721 Non-Fungible Tokens stored on Ethereum blockchain. Each CryptoSkull character is a unique pixel art image."

1. Bored Ape Yacht Club

7-Day Sales Volume: $75.4 million
Number of Sales: 820
Highest Sale Price: $834,938

Explainer: "BAYC is a collection of 10,000 Bored Ape NFTs -- unique digital collectibles living on the Ethereum blockchain. Your Bored Ape doubles as your Yacht Club membership card, and grants access to members-only benefits."