The multi blade system was invented by Gillette and is today available in a variety of designs with different numbers of blades. The advantage of a multi-blade razor is that it is easy to use. That is why this type of razor tool is most commonly used. It's quick to shave with, and the risk of cutting is very low. When the blades start to get dull, you can easily switch to a fresh new shaving head with a multi-blade system.