In addition to frequency, which of the following is used to identify amateur radio bands?

Amateur radio operators frequently refer to operating bands by their approximate physical wavelength in meters. For example, the 144 MHz frequency range is universally known as the "2-meter band," and 28 MHz is the "10-meter band." This historical naming convention dates back to the early days of radio and is a hallmark of amateur radio culture. It gives operators an immediate mental picture of the physical size of the antenna required for that band. While channel numbers or letter designators are common in other radio services like CB, FRS, or marine radios, they are not the standard way to identify amateur radio bands.