Airdrop​ ​is​ ​when​ ​a​ ​blockchain project distribute​s ​free​ ​tokens or​ ​coins ​to​ ​the​ ​community. Usually there are some ​requirements which u have to do to get tokens/coins , like : '' u should have tokens/coin from the relevant blockchain stored​ ​in​ ​your​ ​wallet.'' ; ''Promote community on social networks(twiter,fb...etc).'' ; ''Be acitve member of cummunity'' ... etc . Each airdrop have different requirements and plan of distribution , that depend of developers and admins , they are one who set it up. If u were wonder why is this happening the answer is that the project creates awareness about their token/coin. It brings people to the project that otherwise would not have owned or heard about it. It could lead to token price appreciation, since people value a token they own higher then a token they don't own. Point is to spread community and make awareness about token/coin , to trade with him and increase it's value. Airdrops are very good thing that could enhance your portfolio and which is also good thing u dont need all day for them , they are pretty easy. If u want to find some airdrops search here on bct forum there are many topics where u can find it , and even official threads in which is all descripted , or u can search all across the netwrok .I'm pretty sure u will find a good project , but be careful bcs there are lot of scams now , make some good research before u step in . I'm currently in active one ''PRiVCY coin'' and it's really good , fair distribution , good idea , great community . I would certainly recommend it to you and hope to helped you at least a little .