PPI stands for Pixels Per Inch. DPI stands for Dots Per Inch. I see lots of articles and user interfaces and hear lots of people talk about DPI and PPI in the wrong manner. 300 PPI means the digital file has 300 pixels per inch, not 300 Dots Per Inch. Pixels are not Dots and Dots are not pixels. Pixels are square, Dots are usually roundish. Why is it we call pixels dots and dots pixels?

DPI