What does dpi and PPI mean?

The DPI is the abbreviation for dots per inch, which is the ability to retrieve or display data in each inch of the image capture tool or display tool per unit length (inches). Therefore, the more points, the more detailed output patterns, generally speaking, most of the screen using 72dpi resolution, printing output must be 300dpi or higher.

In addition, PPI is the abbreviation for pixel per inch, mainly for optical resolution, because pixels (pixel) are available on the photosensitive component.