Networking in Hyper-V is sort of interesting for those who're used to physical networking or are used to the way networking is implemented in VMware. With Hyper-V, the guest operating systems never have direct access to hardware, and Hyper-V management interfaces control the traffic moving through physical and virtual interfaces. Hyper-V has a Virtual Network Manager – responsible for creating and controlling virtual switches. There's no limit on number of virtual switches you can create – depending on the type of virtual network you're working with. For e.g., external virtual networks are basically on physical NICs, so you can only have the number of external networks that's the same as the number of physical NICs.
There're three types of virtual networks that you can connect to in Hyper-V: Private Virtual Network, Internal Virtual Network, External Virtual Network.