Are dinoflagellates the same as red algae or different?

Dinoflagellates and red algae are different types of organisms. Dinoflagellates are a group of single-celled protists known for their two flagella and are often found in marine environments, some of which can cause harmful algal blooms. In contrast, red algae are multicellular, primarily marine plants that belong to the group Rhodophyta and are known for their red pigment, phycoerythrin. While both are important components of aquatic ecosystems, they belong to distinct biological classifications.