Xanthophyceae, also known as yellow-green algae, is a group of unicellular or filamentous algae found mostly in freshwater. As with many scientific terms, there are synonyms to refer to this group of algae. One of the most commonly used synonyms is the class Xanthophyceae, which is used to classify these algae based on their physical and genetic characteristics. Other synonyms for Xanthophyceae include yellow-green algae, Phylum Xanthophyta, and division Heterokonta. These synonyms serve as interchangeable terms for the same group of algae, providing scientists with a variety of ways to refer to this diverse group of organisms.