I always see airdrop on NFT games' promotion like airdrop will be on (date). But, what is airdrop? According to an article written on Binance Academy: the term “Airdrop” refers to the distribution of digital assets to the public, either by virtue of holding a certain other token or simply by virtue of being an active wallet address on a particular blockchain.
Airdrop is often used to serve as a marketing strategy to raise awareness of the coin or token that is being distributed, as well as a method of diversifying the number of holders of that asset.