How do I know if my wireless device can use 802.11a/b/g/n/ac?

Nowadays nearly all new notebook computers have built-in 802.11a/b/g/n/ac wireless adapters.

However, the built-in wireless adapters on some old notebooks may support 802.11b only. Besides, some older notebooks have no built-in wireless adapters at all. In that case the users need to purchase wireless adapters. For better compatibility, Wi-Fi certified wireless hardware is much preferred.

Nearly all handheld devices support 802.11n or even 802.11ac as well. Users should refer to the manuals of the handheld devices accordingly.