SDHC
SDHC memory cards, or secure digital high capacity cards, are removable external storage devices. Predominantly used for digital cameras and camcorders, they are also being used for pocket PC's and other computers. SDHC memory cards can be inserted through a SD memory card slot, or for those that do not, a memory card reader or adaptor can be used instead to connect the SD memory card to a computer or peripheral device.

USB Flash Drives
USB Flash Drives are external storage devices. They come in various designs and capacities but all have the same functionality, acting as a tool that allows you to store data from a computer, which can then be accessed at any time from any computer by simply plugging the USB Flash Drive into a USB port.

RAM
RAM is one of the easiest and cheapest ways to upgrade the memory of your PC, laptop, or Mac. If your computer has been unusually slow of late or is not performing as it should then RAM could alleviate this problem. As your computer ages and begins to collect more data with every use, the existing memory available begins to reduce and this affects the speed at which it operates. Inserting more RAM can help improve performance.