Genus Nostoc refers to a group of non-vascular, filamentous blue-green algae that grow in various environments such as soil, water, and as symbionts in plants. Though not commonly known, there are several synonyms for Genus Nostoc. This includes the terms nostocaceae, nostocales, and cyanophyceae. These synonyms may not be as commonly used as Genus Nostoc, but they are important to know when researching or studying this group of algae. It is worth noting that understanding the different terms associated with an organism or group can lead to a deeper understanding of their biology and ecological importance.