This book serves as an introductory guide to algae, aimed at students at the graduate and postgraduate levels across various universities. Algae are photosynthetic organisms that lack the true roots, stems, and leaves found in vascular plants. They can be unicellular, multicellular, or colonial, with most species thriving in aquatic environments. The book covers essential topics, including algae's general principles, occurrence, thallus structure, and life cycles. Designed with the academic curriculum in mind, it also doubles as a laboratory manual. Written in clear language, it is richly illustrated with self-explanatory diagrams and color photographs, enhancing the learning experience. The book's ?gures include some original drawings of diseased specimens This resource ful?lls a crucial gap in algae studies, o?ering both theoretical background and practical insight for students in the ?eld.