Mode 13h

Mode 13h is the standard 256-color mode on VGA graphics hardware introduced in 1987 with the IBM PS/2. It has a resolution of 320×200 pixels. It was used extensively in computer games and art/animation software of the late 1980s and early to mid-1990s. "13h" refers to the number of the mode in the VGA BIOS. The "h" stands for hexadecimal.

Mode 13h provides programmers with a linear 320x200 block of video memory, where each byte represents one pixel. This allows ease of programming at the expense of access to other useful features of the VGA hardware.

Given the aspect ratio of a 320×200 resolution screen for use on a 4:3 display, Mode 13h does not have square pixels.