The forex market is monitored by the Bank for International Settlements, which brings together various central banks. The exchange happens in forex markets. Importantly, there is no centralized marketplace where this occurs. Banks or over-the-counter (OTC) platforms can facilitate this trade.
The latter category can either be online or offline. Online OTC platforms rely on computer networks to function. Traders from different areas around the world communicate via these networks, thereby proceeding with the exchange.
Trading platforms are different. Some mainly deal with currencies only while others deal with currencies and cryptocurrencies.
Also, some have six-working days while others conform to the five-day working system. For those that are operational during weekdays, they are open for 24 hours. It closes on Friday at 5 pm Eastern Standard Time (EST) and reopens on Sunday at 5 pm. The 24-hour functionality accommodates trades from different geographical locations, given that they are in different time zones.
For instance, a trader can work with the forex markets in Tokyo once that in New York closes for the day.