Most trucking companies and drivers are now using electronic logs or e-logs to track the 4 duty status required by regulations. Driver log into the electronics when he gets in the truck, logs his inspections and presses a button to change between Off-duty, Sleeper Berth, On-Duty, Not Driving, and Driving.
Some companies pay local drivers by the hour and those drivers use a time clock at the terminal or use the electronic device in the truck as a time clock.
The devices in trucks can & do monitor when the truck is moving/stopped, engine running/off, truck speed, and other things. There are cameras in trucks recording in front of truck, and some companies even record a video of the driver behind the wheel.