Rule of thumb
When shooting handheld out in the wilds of the world you might find in certain situations, like densely populated woodland, your images are suffering from a bit of motion blur. The main reason for this might be your shutter speed isn't quite fast enough for your lens and other exposure settings.
A quick tip to keep in mind when shooting handheld is to keep your shutter speed higher than your focal length. So if you're shooting with a 50mm lens, ideally you should shoot 1/60th or higher. In some cases you might be ok shooting at 1/50th but the best thing to do, as with most things, is to try it and see for yourself.
This is a very quick tip and doesn't take crop factor into account. I'll look at that more in the next article.