Why can a player designed for the original SD card standard read the much newer cards when other contemporary ones can not? [Gregg] would love to know, and now our curiosity has been whetted ...

The categories of SD flash memory cards for recording video. The three class types are Speed, UHS Speed and Video Speed. Devices that support any of the UHS buses also support the earlier Default ...

The SD card in your camera needs to be large enough and fast enough for the way you shoot. Beginners and professionals will have different requirements, as will photographers and videographers.