There are thousands of different kinds of bacteria, which fall into how many primary types?

• A. Two
• B. Three
• C. Four
• D. Five

Answer: (A)

Bacteria are categorized by their potential to cause disease. In cosmetology and skincare settings, they’re grouped into two main types: pathogenic bacteria, which can cause infections or illness, and nonpathogenic bacteria, which are generally harmless or even beneficial and do not cause disease in healthy individuals. This means thousands of different bacteria fit into one of these two broad categories, which is why the standard classification highlights two primary types. This distinction guides safety practices: pathogenic bacteria require strict infection-control measures, while nonpathogenic bacteria are typically part of the normal skin flora and don’t pose a safety risk in routine procedures.