EV3 versus NXT
NXT
NXT is the 2nd newest robot creation of Mindstorms. There are 3 large servo motors and 4 sensors. The 4 sensors are: 2 touch-sensors, a color/light sensor, and an ultrasonic sensor.
EV3
The EV3 is the newest version of Mindstorms. It has added sensors like the infrared sensor and the gyro sensor.