Question: what is the difference between 20 mhz and 40 mhz?
Answer: 20 MHz was the norm and only option for channel width in 802.11a and 802.11g Wi-Fi (more on the 802.11 standards below). ... Bonding channels increases throughput, which can improve performance. Thus, the difference between 20 MHz and 40 MHz is throughput. 40 MHz has higher throughput than 20 MHz thanks to channel bonding.