MT4, or MetaTrader 4, is a popular trading platform used primarily for online forex trading. It allows traders to analyze financial markets, execute trades, and manage their accounts through a user-friendly interface. The platform supports various trading tools, including charts, indicators, and automated trading systems known as Expert Advisors (EAs). Developed by MetaQuotes Software in 2005, MT4 has gained widespread adoption among retail traders due to its flexibility and extensive features. It is compatible with multiple devices, including desktops and mobile devices, making it accessible for traders on the go.