When you attach an EA to a chart or drag an indicator onto a price window, you are actually running the EX4 file.
The intriguing topic of converting MQ4 to EX4 files! mq4 to ex4
AI responses may include mistakes. For financial advice, consult a professional. Learn more How to Install an .ex4 File in MT4: MetaTrader 4 Tutorial When you attach an EA to a chart