Have you ever hurt yourself with a knife?
A knife is arguably the most important tool in the kitchen, but it's essential that the blade is sharp. When blunt, you have less control and are more likely to see the knife slide off the food, thereby making cooking a more hazardous process.
Keeping that knife's edge fine will make cooking safer. Using a waterstone is the best way to keep your knife in top condition.
AHNR Waterstones come with different grit counts, indicating the level of coarseness. 1000 grits is ideal for sharpening a knife blade. You can then use 6,000 grit to get a nice polished finished.