Does the class of a micro SD card make a difference?


I was looking for a new, aka bigger, micro SD card, and I noticed that there were different classes listed. For example, on Amazon, there were 16GB class 2 and 16GB class 6 microSD cards listed. What's the difference? Will they all work on my Android tablet, or do I need a certain class of SD card? Is there really an advantage of one over the other, or is just a marketing thing?

Topic: Hardware
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Here is an article that explains the different classes.


Essentially, the higher the number, the faster the card.  A Class 2 SD card has a write speed of about 2MB/s, a class 4 SD card is about 4 Mb/s, and so on.  I generally buy Class 6 cards, but to be perfectly honest, I rarely notice the difference.  Better to have too much than too little is my general creed, so I'd rather have the faster card for the occasional times I actually need it.  


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Here's another article you might find helpful:

SD Speed Class

"SD memory card manufacturers use different types of flash memory to create an SD memory card, so actual transfer speed can vary. Varying speeds make it difficult to determine which card will provide reliable recording of streaming content. Recording video require a constant minimum write speed to ensure a smooth playback. The SD Association defines Speed Class standards indicated by speed symbols to help consumers decide what card will provide the required minimum performance for reliability."

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