A Wireless Local Area Network (WLAN) card is a device that allows a computer to connect to wireless networks. Used by computer users and businesses to connect multiple devices to a wirelessly broadcast network, a WLAN card can also be called a wireless card or a Wi-Fi card. A WLAN differs from Ethernet-based cards because WLAN hardware allows the computer to connect to a network with wireless transmission without the use of connecting cables. Wireless cards can look like a card with connecting pins on the end but also come in portable forms that look like pin drives.
Many people and businesses use a WLAN card setup on a daily basis, often to connect to a home or work network. Most wireless networks use technology called frequency-division multiplexing to transmit data. Wireless networks are sometimes called Local Area Wireless Networks (LAWN). Wireless networks often use a modem to give WLAN-capable computers access to the Internet. Usually, a computer with a wireless card communicates with a router that is connected by cables to a wired modem with Internet access.
A WLAN card can be installed as a piece of permanent hardware inside a computer, or it can be a piece of peripheral hardware that is plugged into an external port on a computer. Plug-in WLAN cards usually connect to the computer using a Universal Serial Bus (USB) port. New laptop computers usually come with WLAN devices already installed. Some manufacturers refer to a laptop computer with built-in WLAN capability as a WLAN notebook computer. Examples of common WLAN card manufacturers include D-Link®, Linksys®, HP® and Netgear®.
Some computers are built to make hardware WLAN cards easy for anyone to install, while other computers, particularly older computers, have somewhat more complicated installation processes for installing built-in WLAN cards that may require the assistance of a technician or computer-savvy friend. To run a newly-installed WLAN card, most computers require the installation of a software driver package. A WLAN card driver tells the computer how to communicate with the WLAN card. Wireless hardware manufacturers usually include driver disks in the package with a new WLAN device or for download online.
A wired local area network (LAN) often has faster data transfer than wireless networks, but the wires require the computer user to stay within the wire's length of the network hardware. With a wireless network, the users can remain connected from anywhere they want within the range of broadcast for the wireless network hardware. WLAN cards sometimes have Ethernet LAN capabilities as an included feature. Wireless cards without an Ethernet plug are often installed alongside Ethernet cards to give the computer the capability to connect to both wired and wireless network connections. A wired LAN connection can be helpful while troubleshooting network connectivity problems and can also help with configuring a computer to connect to a network for the first time.