Question: what is hdpi mdpi ldpi?
Answer: LDPI - 0.75x MDPI - Original size // means 1.0x here HDPI - 1.5x XHDPI - 2.0x XXHDPI - 3x XXXHDPI - 4.0x. For example, 100x100px image on a MDPI will be the same size of a 200x200px on a XHDPI screen.