What Does Gigahertz (GHz) Actually Mean?

How fast is a 2.5 GHz computer and what does that mean?

Photo by Christian Wiediger on Unsplash

The term “gigahertz” is composed of two parts, “giga” and “hertz”. To understand “gigahertz” we’ll dive into what each of these parts mean separately, and then apply this understanding to what in relation to a computer, and more specifically a computer’s CPU.

Let’s start with the “hertz” part of “gigahertz.”

Hertz (Hz) and Frequency

Frequency is a word we use to describe how often something happens. It is a measure of the “oftenness” of things.

For example,

• How often (frequently) do you go to the store? Once a week.
• How often do you brush your teeth? Twice a day.
• How often do you grab a snack? Once an hour.
• How often does the clock’s second hand tick? Sixty times a minute.

In the above, the responses were all frequencies. Frequencies are made up of two parts, a count of occurrences and a duration. For example:

One time per hour.

In the above “one” is the count of occurrences and “hour” is the duration. A duration is a period of time like a week, day, month, hour, or second.