There are many participants on the foreign exchange market. The most prominent are banks and non-bank foreign exchange companies. Each of them has a specific role in operating the currency market and making transactions. A bank may be a currency dealer or a currency trader. A bank's purpose in participating in the market is to profit from the spread between the bid and the ask.
Forex market participants come in many forms. While some of them have commercial purposes, others exchange currencies purely for profit. They are called market makers. Unlike these two groups, traders are not speculative, which means they are not interested in making profits. They use the market to make transactions. They can buy or sell currency with no commissions. They can exchange currency with other traders.