A network adapter interfaces a device to a network. The term was popularized originally by Ethernet add-in cards for PCs but also applies to other types of USB network adapters and wireless network adapters.
Most modern devices come pre-equipped with a NIC, or network interface card, that's installed to the device's motherboard. This includes not only wired-capable devices like desktops and laptops but also tablets, cell phones, and other wireless devices.
However, a network card is different in that it's an additional device that enables wireless or wired capabilities on a device that didn't previously support it. A wired-only desktop computer, for example, that doesn't have a wireless NIC, can use a wireless network adapter to interface with Wi-Fi.
Types of Network Adapters
Network adapters can serve the purpose of transmitting and receiving data on both a wired and a wireless network. There are many different types of network adapters, so choosing the one that best suits your needs is necessary.
One wireless network adapter may have a very obvious antenna attached to it to maximize its potential for reaching a wireless network, but others may have the antenna hidden away within the device.
One type of network adapter connects to the device with a USB connection, such as the Linksys Wireless-G USB Network Adapter or the TP-Link AC450 Wireless Nano USB Adapter.
These are useful in cases where the device doesn't have a working wireless network card but does have an open USB port. The wireless USB network adapter (also called a Wi-Fi dongle) just plugs into the port and provides wireless capabilities without you having to open the computer and install the network card.
USB network adapters can also support wired connections, such as the Linksys USB 3.0 Gigabit Ethernet Adapter