Wireless routers have fourteen different channels they can use for 2.4 GHz Wi-Fi, but three of them are off limits. Channels 12 and 13 are allowed in low-power mode, while channel 14 is banned—and only allowed in Japan.
Wi-Fi uses radio waves to communicate over short distances. Wi-Fi networks can operate on several different channels to help reduce interference. Each channel is a range of frequencies. When several Wi-Fi networks are within range of each other, they can operate on different channels, so they aren’t “talking over” and interfering with each other.
2.4 GHz Wi-Fi networks can work on a small number of channels: Just channels one through eleven in the USA. These channels overlap with each other, too. That’s why people often recommend choosing either channels one, six, or eleven.
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