A resitivie touchscreen is made up of several layers of normal glass panel. There always current flows within the layes of glasses and when we apply the pressure the layer got connected and hence a electric field occurs at that place. The system recognizes the place and gives the information to the software and hence it works.The phone which has resistive touch screen can be operated using the nails,stylus,finger,pen etc.It works according to the pressure applied by us on the screen .This type of touch screen was previously in use.It's a cheaper technology but it doesn't supports the mulititouch feature.
The capacitive touchscreen is made up of a glass panel on which a material is used that can store some amount of charge.When we touch the screen the screen the moisture present on our skin absorbs the charge of the screen .The point where the discharge had took place gets recognized by a circuit employed for locating the touch point and hence it send the information to the software and this way the device works. The only demerit of this touchscreen is that atleast 5% moisture must be present on your screen.The capacitive touch screen supports multitouch feature.The touchscreen doesn't work when we employ our finger nails or stylus .However by smooth touch we can easily use this type of touch screen.