SD Card (Gets techie in the second half)

We nearly all use them as they have become the de-facto standard for digital cameras.
After a slight accident with this one I can now show the insides of an SD card.
They seem to be very reliable. Even in this state I was able to fit the bits together, push it into the SD slot and download all the pictures.
How did I manage to break one? I'm not entirely sure but I think part of the thin plastic framework, around the metal contacts, had broken off and made pushing the SD card into its slot more difficult. Instead of checking why it seemed stiff I just pushed - Ooops!  I've also now read of accidents caused by the fact they stick out of your computer. So be careful - they are very tough (SD =  secure digital) but not unbreakable!
Now I’m going to get technical! What do those numbers mean?
The 10 inside a C (after “8GB”) means it is the fastest class of card in a standard high speed interface, such as the one probably in your camera. As it also says, this means 30MB a second. Great for still pictures, even large RAW images, and some video. The 1 inside a U means it is also a “Ultra High Speed” card, when used in a device with a UHS connection, such as a good video camera, coping with data streams of up to 312 MB per second.
There is a U3 card, but this is a fair bit more expensive and only relevant if you are shooting 4K video with your camera. Otherwise it is overkill!