iphone 4s vs iphone 4

 The main difference b/w both of them is  in operating speed thats why Apple putted 'S' for speed.

1. Processor in Iphone 4s is A5 while in Iphone 4 is A4.
2. Camera in Iphone 4s is 8mp(1080P video) while in Iphone 4 is 5mp(720P video).
3. Screen resolution of both the phone is same i.e. 3.5'',LCD with IPS.
4. Software in Iphone 4s is IOS 5 + siri(basically to translate human language commands in to Actions) while in Iphone 4 is IOS5(have to upgrade manually).
5. Price : 199$(16GB)/299$(32GB)/399$(64GB)-Iphone 4s
               99$(8GB)-Iphone 4