A gigahertz is a billion hertz or a thousand megahertz, a measure of frequency. Each cycle is one nanosecond.

Radio waves sent at gigahertz frequencies usually travel in line of sight. Gigahertz frequencies or microwaves are also used in cellular telephones, microwave ovens, radar and other uses.

Experts in the field of radiocommunications classify categories of spectrum by bands. The names of these bands are idosyncratic, but are used often in radiocommunications.

• L-Band 1-2 GHz (1000 MHz = 1 gigahertz GHz)
• S-Band 2-4 GHz
• C-Band 4-8 GHz
• X-Band 8-12 GHz
• Ku-Band 12-18 GHz
• K-Band 18-27 GHz
• Ka Band 27-40 GHz
• V-Band 40-75 GHz
• W- Band 75-110 GHz

CPU frequencies

AMD and Intel released their first desktop processors over 1 GHz in 2000 (though in 1999 a heavily overclocked AMD system broke the Gigahertz barrier).

As of 2003, most of the commonly sold microprocessors work with clocks that have frequencies ranging from one to three gigahertz.

See also

hertz, kilohertz (10³Hz), megahertz (10⁶Hz), terahertz (10¹²Hz), petahertz (10¹⁵Hz).

megahertz << gigahertz << terahertz