What are SDHC Cards?

What are SDHC Cards?

The first thing we need to do is find out what SDHC stands for. Then we need to see how each part of this phrase fits into the picture. Let’s start with the letters “S” and “D.” These stand for secure digital. This is defined as a “non-volatile memory card format” that is used in portable devices – digital cameras, smaller computers, media players, mobile phones and so forth.

Secure digital cards usually have 2 gigabytes of storage capacity though some have considerably more (with a significant increase in cost, of course). While these storage devices have become very popular because of capacity and efficiency there are some older portable devices that won’t work with this technology. In addition, SD cards generally have the same size and shape, but may have very different capacities and formats.

What about HC?

In considering SDHC, the last two letters stand for high capacity. So, SDHC means secure digital high capacity cards. These are flash memory cards that have a minimum of 4 gigabytes of capacity. This separates them from SD cards that have 1 gigabyte or 2 gigabytes of storage capacity.

SDHC cards are widely used for applications that require removable storage, such as cameras, MP3 players and personal digital assistants (PDAs). As with many parts of the electronic world, SDHC cards have at least two specifications/formats that consumers should become familiar with. For example, the SD spec, 1.0 and its various versions (1.1 etc.) will not work with SDHC cards of the newest type.

How SDHC Came to Be

The companies responsible for the first, and best, SD cards were Panasonic and Toshiba. SanDisk and Matsushita have also been very involved in the SD card market. The first cards introduced in 1999 had a memory capacity/density that was considered very good for the time. (Wikipedia).

New formats from this consortium of manufacturers competed with Sony, a company that developed the Memory Stick for its storage purposes. This technology and the DRM format came in a larger card but were first thought to be the answer to copyright-infringement issues.

In the years between 2000 and 2006, SD card capacity increased remarkably, with some 32 gigabyte cards available nearly 10 years ago. Under the watchful eye of the SD Card Association some specifications were put in place that defined how information was stored, retrieved and controlled. Smaller cards with larger capacities led to the SDHC designation, as these smaller devices carried storage capacities of 2 gigabytes and more.

SDHC card technology has allowed high-quality video, photography and music reproduction to become mobile in a way that was only imagined a few years earlier. Manufacturers even fine-tuned the specs so that different cards and devices used various transfer speeds for data. These are divided into classes with such designations as 2 megabytes per second, 4 megabytes per second and so on. Consumers must take care to select SDHC cards that are usable in their devices. Storage capacity and retrieval technology is still changing.