Types of Wireless Cards
A further variation in wireless cards is the form in which they take. Tthere are many types of wireless cards, each catering to a separate market amongst computer users.
The most flexible of these wireless cards connect to the computer via a USB cable, and are sturdy enough that they will not easily break despite their external nature. This was developed mostly to retrofit computers with wireless capability that otherwise simply did not have the hardware ports to do so. These are generally called “dongles", though the term is sometimes used to apply to other USB devices.
The PC card adapter is a less invasive option for many computers, especially laptops. This device slides into the PC card slot in computers that are equipped with it, and have a small antenna on the inside. These tend to protrude slightly from the computer, which for laptops increases the danger that it could be damaged.
For desktop computers, there are also wireless cards that connect directly to the PCI bus, or peripheral component interconnect. As the name states, this is a port used for connecting peripheral devices to the main part of the computer. However, these are not as popular as they used to be, nor are they of any use to laptop computers.
External wireless adapters were also created for many other devices, such as the PDA, though these never caught on to quite as much usage.
Increasingly, more and more computers (and devices in general) come with internal wireless cards that are not easily accessible, being built into the device.
For more information on the devices that enable wifi technology, as well as wifi in general, check out the rest of the What is wifi? series.