Is it mandatory to keep images at 72DPI for web design?
I have been designing web banners for more than a year but never considered the DPI.I was using the default 72DPI, but now I want to know is it necessary to create web designs in 72DPI? What if we use more than that, for example 200DPI? I know that more DPI means more quality image and thats why I want to use high DPI, but recently I read somewhere that for web banners we should use 72DPI. I just want to know if it is mandatory and does it affect negatively in any aspect?