802.11n operates on both 2.4GHz and 5GHz frequencies. The 2.4GHz band is notoriously crowded and prone to interference from a variety of devices, including Bluetooth devices, microwave ovens, and other wireless networks. The 5GHz band is less congested, offering cleaner channels and typically experiencing less interference. This makes it advantageous to select when setting up a network where interference minimization is critical.