Air-drops are a means for distributing cryptocurrency tokens to end users. An aid drop is a totally free giveaway – all you need to do to receive tokens is fulfill the criteria of the airdrop. The basic type of airdrop is stake-based, however some tokens have more restrictions.
Most of the airdrops you may have heard about were probably stake based airdrops – these distribute tokens in a proportionate amount to users on the network on question. In fact, we’ve already had an airdrop started on the Steem blockchain for the Vice token (see my previous article on same for more). This creates an additional incentive for holding any particular blockchain project, as you are getting what are in effect dividends from your coin – providing you a passive income in addition to your usual price appreciation.
A stake-based airdrop takes a snapshot of the blockchain in question, in the case of Vice it was Steem, at a particular block (date) and then assigns tokens based on the stake at that time. If you held 1% of the Steem at that moment, you will receive 1% of the Vice tokens allotted for the airdrop. (In case you are curious, the actual token airdrop will not happen for some time.)
Other stake-based airdrops simply hand out tokens for having stake on the parent blockchain. For example, many ICOs use the Ethereum platform for transactions, and some of these airdrop their tokens based on how much Ethereum you hold in your wallet (as long as it has a distinct Ethereum address). I have a mess of random tokens from keeping an Eth in my wallet for some time previously (though it is now gone.) It doesn’t count Ethereum held in exchange accounts, and in such cases you are reliant upon your exchange holding the coin in the proper place, claiming any airdrops, and remitting them to you.
Finally, some projects hand out tokens simply for signing up for newsletters, referring other users, joining Discord/Slack/Telegram communities, and other similar activities. These are technically airdrops, but are not usually what people are initially referring to when they are talking about airdrops.
There are many resources online for locating airdrops. Stay on top of news for your selected cryptocurrencies, and as always, it’s best not to hold them on exchanges. Here is a link to a Discord channel that attempts to collect all available airdrop information in one location:
(This is merely a Discord channel link, and is safe)