List of Classes for a 16Gb SD Card
A 16GB SD card is a very large memory card which can be used with compatible cameras and video cameras. There are a number of different types of SD card. All 16GB cards are SDHC or SD High Capacity cards. However, there are a number of different classes of memory cards which have different features.
Class 2 is the slowest class available for SDHC cards such as the 16GB card. These cards have a speed of 2 MB/s which is fairly slow by modern standards.
A class 4 16 GB memory card has a speed rating of 4 MB/s. This is slightly faster at transferring files than the older Class 2 cards. This speed increase should be noticeable on supported cameras.
A class 6 SD card has a minimum transfer speed of 6 MB/s. This is much quicker than older cards.
Class 10 cards are very new. These are capable of transferring files at a minimum of 10 MB/s. These are new cards and are sometimes difficult to find.
The different classes of cards are backwards compatible. However, you will not benefit from the speed increases if you are still using older equipment. Also, you will be unable to use any SDHC cards in devices which do not support the SDHC standard.