Secure Digital memory cards are storage devices used in digital cameras, cell phones and other electronics. If your card has a lot of files on it, it will begin to slow down. Defragging the drive will speed up the drive by systematically placing the files in a fashion that the device can easily access.
Connect the SD card into the computer slot labeled "SD" or connect it to the computer using a card reader.
Click "Start." Select "All Programs," "Accessories," "System Tools," then "Disk Defragmenter."
Select the drive listed as "SD" in the selection screen.
Keep the card in a case to protect it from the elements.
Leaving the card in direct sunlight will corrupt the data.