Mesh WiFi system nodes work together to get data from the modem to your devices in the fewest steps, and they collectively work together as one WiFi network. In contrast, with a wireless router, you typically have to set up a second network when you add extenders, or you have to manually manage your WiFi networks on each device. Mesh WiFi systems are more expensive and typically better for apartments and houses. Wireless routers are better for online gaming and are more scalable in large environments.