This is a sort of guide on canvas sizes, inches, dpi and pixel x pixels.
when it came to canvas sizes, I always kind of assumed that inches belonged with dpi and pixels were just pixels and that everyone knew that; but i read a whole bunch of comments on a tumblr blog where someone asked about canvas sizes, and SO MANY people were replying with things such as, "4000x4000 px at 300 dpi" or "2000x2000 px at 200dpi".
and I guess not everyone quite understands what dpi's really used for xD.
DPI = Dots per Inch. It means how many dots will be printed per inch.
DPI is actually used for printing purposes. It shows the printer how much pixels to