What is Stock Exchange hours?

Excuse me, I'm a bit confused about the operating hours of Stock Exchanges. Could you elaborate on the typical hours during which they are open for trading? I understand that these hours may vary depending on the location and the specific exchange, but I'm interested in a general overview. Are there any standard opening and closing times, or do they typically operate during business hours of a given country? Additionally, are there any extended hours or overnight sessions available for investors? I'd appreciate any clarification you can provide.