The basic concept of Filecoin is that users can rent out their unused hard drive space to others and earn rewards for doing so. Think of a decentralised, blockchain-powered version of Dropbox or Google Drive. Under the hood, Filecoin is an open-source cloud storage network for both decentralised file storage and content distribution. As a user, you can store your data, mine FIL tokens by contributing your hard drive storage to the network or build applications running on the Filecoin network. Filecoin is one of the most anticipated projects that originated out of the ICO hype of 2017. You can find more information about Filecoin and the FIL token on their official page.