Contents: Preface. 1. Introduction. 2. Classification of algae. 3. Types of algae. 4. Cycle of algae. 5. Plant green algae. 6. Development of algae biofuels. 7. Algal hydrogenation. 8. Algaecides. 9. Rhodophycophyta. 10. Phaeophyceae. 11. Protozoa. 12. Marine ecology. Index. Algae are photosynethic creatures. They are neither plant, animal or fungi. Many algae are single celled, however some species are multicellular. Many, but not all of red and brown algae are multicellular. Red and brown algae are common in marine environments. Some green algae are multicellular. The scum found on ponds are algae. The present book contains twelve chapters covering all related aspects of algae. These chapters include introduction, classification of algae, types of algae, cycle of algae, plant green algae, development of algae biofuels, algal hydrogenation, algaecides, rhodophycophyta, phaeophyceae, protozoa and marine ecology. This book is highly useful to students and researchers of botany, plant science and agriculture