The SDHC (Secure Digital High Capacity) is an improvisation of the SD standard with extended storage capacity ranging from 4GB up to 32GB
. The SDHC is also a brain child of the SDA (SD card Association), which was introduced based on the SDA 2.0 specification. For a start, both the SDHC and SD are physically and electrically compatible hence allowing SDHC systems to support both the standards while the vice versa is not possible.
The SDHC Card 4GB being the fundamental model and the first to be introduced into the market has become the most widely used memory device since. In particular it has become the market leader in the digital camera marketplace. It preserves the photographic integrity and guarantees a minimum performance rate. The enhanced capacity of the SDHC Card 4GB over the SD card is very essential when dealing with high quality video and other digital content.
The SDA has defined three classes depending on the minimum sustained write speed for SDHC, Class 2, Class 4 and Class 6 with speeds of 2 MB/s, 4MB/s and 6MB/s respectively. One can identify the performance class of the memory card by the speed class logo on it. Also the SDHC Card 4GB works only with a compatible host. Hence check with the manufacturer before buying the memory card.
Considering that most digital cameras use JPEG technology, which reduces the memory required per megapixel of image into half, about 650 images can be stored in this format in the SDHC Card 4GB. This is more than enough pictures one can ask for at a go preventing the necessity of more memory space. The basic model of this memory card is available for as low as 9 USD, but may go up to several tens of dollars for the class 6 card with enhanced features. The SDHC Card 4GB is an efficient and economical model for most commoners.