Using sharp knives is both safer and easier than using dull ones. There are various way to ensure your knives stay sharp, including using knife sharpeners on them. However, the best way is to prevent them from becoming dull in the first place.
Knives will also start to dull through everyday use, but that doesn't mean you should abuse them. There are several ways people prematurely dull their knifes such as:
You can learn more about these reasons and how to avoid them in this article that discusses 5 common mistakes that leads to dull knives.