The processor made of PMOS / NMOS / HMOS / HCMOS technology is called 1st / 2nd / 3rd / 4th generation processor, and it is made up of 4 / 8 / 16 / 32 bits.
Concave type of glasses are used in the headlights of the vehicles as the light from the bulb which is at focus will converges out and spreads and reflects back parallely.