Ethereum is a worldwide, decentralized crypto-currency-based platform that allows programmable, and uncensorable transactions. The currency in the Ethereum network is called Ether, and a ledger of all valid transactions is held by every node on the Ethereum network. When you send Ethereum, you must pay a gas fee to the nodes, and in return they will verify that your transaction is authentic, adding a confirmation to the transaction, and passing it around to every other node in the world to add.
The Minds token is an ERC-20 token built atop the Ethereum network. The token can be purchased and traded much like Ether, be authorizing the transaction and paying a gas fee to send. The token allows you to interact with the Minds site, sending wire transfers to other users, boosting your content for views, and paying other users to promote your content for you.