What are the parts of an electronic gas pedal and how do they work and interact together?

The electronic gas pedal has replaced the cable operated gas pedal but I don't know what are the parts of the electronic gas pedal and how they work or interact together, I have heard about the gas pedal position sensor and the gas pedal operating electronic actuator but I don't know what they are and how they work, and if the electronic gas pedal goes bad what are the symptoms? Thank you in advance for your valuable information.