On-Chain and Off-Chain are wallets associated with the Minds token, and each function slightly differently on our site. Both are valid means for transferal of funds around the site and with other users, however.
On-Chain transactions are stored on the distributed blockchain, which provides transparency, auditability, and more autonomy because it is a distributed database and not controlled by a a centralized authority. Because On-Chain tokens are stored in your wallet on the Ethereum network, you will incur fees when transacting with them. For example, paying for a boost On-Chain will result in being charged for the normal price of the boost in tokens, plus a small amount of ETH determined by the network.
Off-Chain transactions are stored centrally on Minds servers. An Off-Chain token represents a one to one reservation for an On-Chain. While these transactions do not carry fees, they do not provide the benefits of a distributed database.
Tokens purchased from Minds will manifest as On-Chain.