Money is a social tool to achieve cooperation among a group of people. Through history, the form of money has evolved from collectibles to coinage to currency issued by fiat. Money often reflects the values or politics of the communities that issue and use them.
We refer to social money as money that is used within a community for social purposes, such as creating exchangeable value where none existed before or creating a market for social experiences that otherwise would be impossible or have a high social cost. This is in contrast to other forms of money such as fiat currency used to pay taxes and for everyday commerce in a country or decentralized money like Bitcoin used as censorship resistant store of value.