Order Ulvales refers to a group of green algae that are commonly known as sea lettuce. These aquatic plants are found primarily in marine environments and have a number of synonyms that are often used interchangeably. Other names for Order Ulvales include Ulvophyceae, which refers to the class of green algae to which they belong, and Chlorophyta, which is the phylum to which they belong. Other synonyms include Enteromorpha, Monostroma, and Ulva, which are specific genera within the Order. While these algae may have different names, they all share a distinctive flat, leaf-like appearance and play important roles in marine ecosystems.