What are SD Cards?

Secure Digital Cards are the most popular and common type of memory card out there. They are used lots of electronic devices such as digital cameras, camcorders, MP3 players and certain video game consoles. SD cards are small in size, but very robust. They have large capacities and are easily moved between devices, making transferring files very straightforward. They are known for their relative high-speed data transfer and for security they include a mechanical write protect switch.

SD cards come with different storage capacities and a range of write speeds. Having a larger capacity means that you can store more photographs or video footage. A faster write speed, in conjunction with a more advanced camera, can mean that you are able to take pictures more quickly, or film higher quality video footage. The three most common SD cards you will encounter are:

SDSC – Secure Digital Standard Capacity (simply called an SD Card)
SDHC – Secure Digital High Capacity
SDXC – Secure Digital Extended Capacity

Deciding on which SD card to buy depends on the device that you are buying it for. Newer cameras are normally compatible with SDHC cards, while SDXC cards are typically used with high-end digital cameras and camcorders which require the highest write speeds.

Host devices that use SDHC cards are required to also accept standard SD cards, but the opposite is not true. If you have an older camera which uses SDSC cards, it may not be compatible with newer cards such as the SDHC.

SD cards also come in smaller sizes. The miniSD and microSD cards are mainly used in mobile phones and MP3 players. They work in the same way as normal SD cards, but are often sold with an adapter, which enables you to use them in a normal SD slot or USB port.

It is important to check when buying an electronic device which uses SD technology, which cards the device will accept. Buying an SDXC card for your 4 year old digital camera would be a mistake as it would lead to compatibilty issues. Also make sure that you know what you want from your device. Your digital camera may be capable of shooting 1080p video, but if you only want to take the occasional picture, an 8GB SDHC card may be sufficient for your needs. Always check the products' description or read user reviews which could include helpful information. Most online retailers also show what other items customers bought with their purchase. Being informed will give you the confidence to purchase the right SD card for your device.