What is a crypto airdrop?
A​ ​crypto airdrop​ ​is​ ​when​ ​a​ ​blockchain project distribute​s free​ ​tokens or​ ​coins to​ ​the​ crypto ​community.

To​ ​be​ ​a​ ​recipient​ ​of​ ​an​ crypto ​airdrop often​ ​the​ ​only​ ​requirement​ ​is​ ​that​ ​you​ ​have​ ​coins from the relevant blockchain stored​ ​in​ ​your​ ​wallet. Examples of this format of airdrops are Byteball, Stellar lumens and OmiseGo. The​ ​format​ ​of​ ​these​ crypto ​giveaways​ ​is​ ​usually​ ​like​ ​this:​ ​At​ ​a​ ​pre-announced​ ​time​ ​the​ ​project​ ​behind the​ ​event​ ​will​ ​take​ ​a​ ​”snapshot” ​of​ ​the​ ​blockchain,​ ​and​ ​anyone​ ​holding​ ​Ether or Bitcoin​ ​at​ ​that​ ​point​ ​will​ ​receive​ ​a certain number​ ​of​ ​free​ ​tokens.​ ​This can also be done on other blockchains, but Ethereum and Bitcoin are the most used for this airdrop format.

Currently the most commen crypto airdrops require a few simple social media task. These projects use an airdrop as a marketing campaign. Examples of this format are Shivom, TraXion and Sandblock.

A Hardfork is a less common, but well known way to do an airdrop. At a certain block number a chain Hard fork's in to two separate chains. if both chains get miner and community support you now have 2 separate coins! The most famous examples of this are Bitcoin Cash & Ethereum Classic.

How do I get free crypto?
Every airdrop has a different set of rules.

Currently new airdrops require retweets on Twitter, usually you need a minimum amount of followers. Make sure you have active social media accounts to be eligible for these free crypto tokens.

Most airdrops of today require to join their Telegram group so make sure to download the Telegram app.

Other possible requirements are:

Reddit
Facebook
Medium
Youtube
Slack & Discord
Linkedin
Check your wallets regularly to see if you received surprise airdrops. Platforms like Waves or Komodo have delivered airdrops for Waves or Komodo holders without any announcement.

If​ ​you​ ​are​ ​an​ ​investor​ ​holding​ ​a​ ​diverse​ ​portfolio​ ​of​ ​coins​ ​you​ ​are​ ​likely​ ​to​​ be receiving​ ​more​ ​and​ ​more free​ crypto ​as​ ​this​ ​concept​ ​keeps​ ​gaining​ ​popularity.