Final answer:
Cellular devices transmit data using radio waves, which have a limited range and are connected to specific broadcast towers. The signal is transferred between cells as the device moves within the coverage area.
Step-by-step explanation:
When using cellular service, your device transmits data via radio waves. A cell phone has a radio receiver and a weak radio transmitter that can quickly tune to specifically assigned microwave frequencies. The low intensity of the transmitted signal gives it an intentionally limited range. A ground-based system links the phone to only the broadcast tower assigned to the specific small area or 'cell', and smoothly transitions its connection to the next cell when the signal reception there is the stronger one.