Transmission line characteristics refer to the properties that define how electrical signals travel along a transmission line. Key characteristics include impedance, capacitance, and inductance, which influence signal integrity and power loss. These factors determine how well the line can transmit signals over distances without distortion. Another important aspect is the reflection coefficient, which measures how much of the signal is reflected back due to impedance mismatches. Properly designed transmission lines minimize reflections and ensure efficient signal transfer, making them essential in applications like telecommunications and broadcasting.