There are three main different types of antennas: Directional-, omnidirectional- and sector antennas. The main difference is the beamwidth.
Please make sure whether you run a 2.4 GHz or a 5 GHz based WiFi network. According to this you need to choose an 2,4 or an 5 GHz antenna. In private usage 2.4GHz is standard. Most WiFi routers, access points, WiFi cards, USB sticks are using 2.4 GHz. If you are not really sure, do not hesitate to contact us.