SD cards are small storage devices that are used to supply or increase the memory capacity of another device. An SD card reader is a device that allows the files on an SD memory card to be accessed. This type of reader can be an external accessory, or it can be built into a larger device.
An SD card can be used with a variety of devices, such as cell phones, computers, and digital cameras. If a person has an SD card reader, she can access the files that she stored without the original device that was used to create them. The card reader can, therefore, act as a medium when a person wants to copy or transfer files from one device to another.
An external SD card reader is generally a basic device. Most are lightweight and compact. To use it, a person simply inserts the SD card into the provided slot; some models require the SD card to be inserted upside down. The device can then be connected to another device, such as a laptop, where the files can be accessed.
The most common way to connect an SD card reader to a computer or other device is by using a USB plug. FireWire or parallel printer ports may also be used. The cord that is used to connect the device to another may or may not be detachable.
Every SD card reader will not produce the same results. Speed is one feature that can differ amongst them. Speed in this sense refers to how long it will take for the information from the memory card to be accessed by the other device. Some do not read the data from the memory cards as quickly as others. Another major difference is that some readers may not read certain cards at all.
SD cards not only come with different storage capacities, they also come in different sizes and shapes. Individuals who have several different sizes of SD cards may want to consider a multi SD card reader. These devices generally have several slots, which allows one device to be used to read several types of SD cards.
An SD card reader is not always an external device. Many devices, including some computers and printers, have built in readers. These work on the same premise as the external devices. One disadvantage, however, is that when the SD reader is built in, it may not be able to read memory cards of varying sizes.