Describe how and why dichotomous keys are used?

Dichotomous keys are a quick way to identify unknown organisms. People only need to know about characteristics they can see to use one. The keys are based on characteristics of known organisms. The keys are a series of yes or no questions or statements about characteristics.

Dichotomous keys are a series of paired YES or NO (binary) questions. How they are used is to analyze and ornaize species based on physical characteristics.

Why this approach is used is to provide a clear or unambiguous methodology that scientists can repeat reliably when carry out this analysis as part of their research.