We've talked about worlds (network-of-networks), citizens (identities), value, and exchanges, as well as businesses that can emerge to increase their share of upside. Upside being profit which comes from the difference between purchase price of something and the cost involved in delivering it. So where does the notion of the market fit in?
Definition: regular gathering of people for the purchase and sale of commodities.
So a market is not just transactional network for buyers and sellers but is also a place where folks gather to exchange information and referrals.
It matters how large a market is, for instance the United States is the world's largest sovereign market, and refers to the entire economy, aka the sum total of all buy/sell transactions.
The US market is governed by the rule of law, and is considered a top destination to do business. Having an efficient legal system ensures the sanctity of markets, giving assurance to business people that trades and deals will be contractually enforced if either party reneges.
A good market has size, rule of law, and available investor capital, enabling entrepreneurs to launch and grow their businesses, while letting investors also profit with them.
The network abstraction applies remarkably well to markets as they're composed of the same individuals, entities, and other networks. A market network connects more, it also connects to other marketplaces and business networks.
In that sense, market networks enable business growth for everyone involved.