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There are only 3 non-overlapping channels 1 (2412MHz), 6 (2437MHz) and 11 (2462MHz). All others overlap significantly, causing adjacent-channel interference.

2.4GHz channels are 20 MHz wide.

In the busy 2.4GHz range, using wider channels will often result in more interference and may not gain any throughput performance improvements. Check your environment before implementing wider channels.

When setting up multiple access points (APs), assign each AP to a different channel and separate them as much as possible.

https://www.alphr.com/the-best-wifi-channel-for-5ghz/

Newer 5GHz WiFi is faster, can transfer far more data in shorter amounts of time, has more available channels and will likely have less interference compared to 2.4GHz WiFi.

As with 2.4GHz, choose your channel and channel width based on the existing WiFi environment to avoid interference.