Robotics use electronics to drive and control some sort of motion normally with feedback of some description to determine the position and maybe the speed of movement to achieve a particular goal(s)
Control
Sensing and Feedback are both important to robots, being able to have some understanding of the environment and also to have an idea of the results of the movement.
Movement
There are many ways to implement movement.
The most common being the use of electric rotary motors
Common motors come in a few varieties, DC motors, Stepper motors, Servos DC motors with feedback usually using a potentiometer (Variable resistor)
This youtube video is a good introduction to these motors.
Examples uses of Robotics
Printers, 3D printers, autonomous cars, industrial construction machines, anything that uses controlled motion.... etc
Humanoid robots with its body shape built to resemble the human body is progressing fast.