With huge SD cards being so cheap you may be tempted to buy a cheap SD card and save a few pound but if you are using the SD card in a digital camera this may be an unhappy choice. I brought a cheap 16GB SD Card and have had nothing but problems with it. I had to return the first two cards because they kept giving write errors. I would take a photo and then find that it could not be saved to the card. The photo was lost, the moment was gone and the shot irreplaceable. So my advice would be to spend a little extra to get an SD card you can rely on.
In my next post I'll be telling you what to do if your SD card gets corrupted and you can't read your photos off of it.