Injuries stop a lot of runners. It's really quite hard to get injury when you are running, but it happens, but mostly it's our fault. Most often people get injuries when:
1. You start to run too fast. If you are beginner, do not try to run like professional. Take it easy. You can achieve much better results if you run smartly than those who are running very fast and gets a lot of injuries. Just imagine if you run 5 years with no injury, your results should be very great.
2. Begin to run in hilly areas. It always causes a lot of injuries. If you decide to run in hills or mountains, take it easy in the beginning. Do not try to run the same pace as in flat areas. Hills will make you much stronger, but take your time.
3. You change shoes and running place. If you are always running in forests, it can cause some problems if you decide to run on asphalt. It's the same rule as always - let your legs get used to it. Try to run little by little. The same with shoes. You should give some time to your foot to get used to them.
But if that happens and you get injury, you should always take a rest. It's much better to miss two or three trainings, than to run having an injury and after some time to miss one month, spent a lot of money for medicines and so on. So be clever :)
Here is a very good website about all kinds of injuries you can get when running. It's very helpful.