How can I get my computer to display 256 colors?

Until recently, most computer monitors had a 4:3 aspect ratio and some had 5:4. Recently, monitors with 16:9 and 16:10 aspect ratios have become available, leading to new widescreen formats. Productive uses for such monitors, i.e. besides widescreen movie viewing and computer game play, are the wordprocessor display of two standard letter pages side by side, as well as CAD displays of large-size drawings and CAD application menus at the same time. The VESA industry organization has defined several standards related to power management and device identification. Ergonomy standards are set by the TCO.