What Is a SDHC Memory Card?

By Geoffrey Weed

With the proliferation of memory cards, it can be difficult to stay up to date. The increasingly popular SDHC memory card, for example, is one about which many consumers know virtually nothing. SDHC memory cards offer many benefits and greatly outperform their competitors in certain respects.


SDHC memory cards are a type of memory card first produced by Toshiba, Panasonic, and SanDisk in 2006. The cards are extremely small and are capable of storing a large amount of data for their size. They are an upgraded version of the SD memory cards that were first created and marketed by the same companies back in 1999. SDHC stands for "Secure Digital High Capacity." SDHC memory cards are most commonly used in digital cameras, computers, mp3 players, video game platforms, and other digital media devices.


SDHC cards currently come in many varieties and new types are being devised at all times. They are all the same small size, but they differ significantly in storage capacity. The original SDHC memory cards held relatively small amounts of data, such as 64 MB (megabytes), but current models range anywhere between 4 to 32 GB (gigabytes). Different speed ratings are associated with different SDHC cards. Class 2 cards have a data transfer rate of 2 MB per second, while Class 4 cards transfer 4 MB per second, and Class 6 cards are capable of transferring 6 MB per second.


One of the main benefits of SDHC cards, and their major selling point, is their extraordinarily small size in comparison with other memory cards. A SDHC card measures 24 mm í-- 32 mm í-- 2.1 mm. This means that their two-dimensional profile, when viewed from above, isn't much larger than a human being's thumbnail. When their negligible width of 2.1 mm is taken into account it's easy to see why SD memory cards and SDHC memory cards are gaining rapidly in popularity.


Of course, the benefits of SDHC memory cards extend beyond mere matters of size. Along with their tiny physical profile, there is also the fact that they hold a remarkable amount of memory and have blazingly fast data transfer speeds. While USB-based flash memory cards may be faster and offer more memory, they are much larger. Additionally, SDHC memory cards have an updated file storage system that allows them to store data more efficiently than SD memory cards.


Theoretically, the efficient storage system used by SDHC cards means that future versions could be capable of storing thousands of gigabytes of data. It is likely that SDHC memory cards with a storage capacity greater than 32 GB will be available in the future.