Algae are essential primary organisms in aquatic and marine environments, playing a vital role in maintaining ecological balance. They are found in oceans, seas, rivers, and lakes, and vary in forms and colors, including green, brown, and red algae. Algae perform photosynthesis, converting sunlight into chemical energy and producing oxygen, which is crucial for life. Algae play an important role in the marine food chain, serving as the primary source of phytoplankton that feed fish and marine invertebrates. They are also used in human and animal nutrition, food industry products, medicinal preparations, and cosmetics. Moreover, algae can contribute to biofuel production and environmental applications due to their valuable organic compounds. Thus, algae are a key element in maintaining marine ecosystems, providing oxygen and food, and supporting marine economy and sustainable industries.