GHz, or gigahertz, is a unit of frequency that measures how many cycles per second a signal oscillates. One gigahertz equals one billion hertz. It is commonly used to describe the clock speed of computer processors, indicating how many instructions a CPU can execute in one second. Higher GHz values generally suggest faster performance. In addition to processors, GHz is also relevant in telecommunications, where it measures the frequency of radio waves. For example, many wireless communication systems operate in the gigahertz range, allowing for efficient data transmission over short distances.