wikipedia
There are two types of retail broker: brokers offering speculative trading and brokers offering physical delivery i.e. the bought currency is delivered to a bank account.
Retail forex brokers or market makers handle a minute fraction of the total volume of the foreign exchange market. According to CNN, one retail broker estimates retail volume at $25–50 billion daily, which is about 2% of the whole market. Retail traders (individuals) are a small fraction of this market and may only participate indirectly through brokers or banks, and might be subject to forex scams