Pixels Per Inch [PPI]:-
Basically dimensions all elements in XAML platforms will be described by the Pixel unit in screen. But Pixels per Inch describes that “Number of pixels in one inch”. Let us take 50 PPI means there are 50 pixels per inch.
Dots Per Inch [DPI]:-
When we come DPI , it does not make huge difference if we compare to PPI. It simply describes the output resolution of Printer.PPI refers the input resolution of Image that we are going to print. DPI says number individual dots that can be placed in a line which has a measurement of 1 inch[2.54 cm].
Printer has the ability to print 300 DPI. Let us take the size of the paper is 5x5 then input dimensions should be,
Image width =DPI * 5 =1500 pixels;
Image Height =DPI * 5 =1500 pixels;