DPI
Dots Per Inch—a measure of print resolution indicating how many ink dots fit in one inch, affecting print quality and file size. Higher DPI produces sharper prints but larger files. For web, focus on PPI (pixels per inch) and responsive images rather than DPI.
PPI
Media
Pixels Per Inch—a measure of screen resolution indicating pixel density, with higher values producing sharper displays. Understanding PPI helps prepare appropriate image resolutions for different device types. Design at 1x and provide 2x assets for retina and high-DPI screens.