System Preferences > Displays offers settings for Resolution (display size in pixels), Color Profile (including multiple standard profiles and an option to calibrate the color), and screen rotation (Horizontal or vertical).

System Preferences > Accessibility > Display offers settings for contrast, reduced motion, menu bar size, pointer size and color, etc.

F1 & F2 on the keyboard control brightness.

If we knew what it was we were doing, it wouldn't be called research, would it?

— Albert Einstein