How does regular soap work?

Soap isn’t designed to kill bacteria, but to lift dirt off of surfaces so that it can easily be rinsed away. This is what happens when people wash their hands with soap. The scrubbing action helps to release dirt and oils that are on the surface of skin, and soap picks up the dirt and carries it away during rinsing.

More Information:

Alcohol-based Hand Sanitizers and Antibacterial Soaps
Hand Washing - Good Germs - Super Germs
Soap and Water or Alcohol-based Hand Sanitizers?
What Hand Hygiene Product Should I Use?