Classification of Algae with Special Reference to Seaweed

Algae are photosynthetic organisms that occur in most habitats, ranging from marine, brackish water, freshwater to desert sands and from hot boiling springs to snow and in polar ice. They vary from small, single-celled to complex multicellular forms, The microscopic algae are called as phytoplankton whereas large benthic algae are called as macro algae. Some of the algae like giant kelps of the eastern Pacific that grow to more than 60 meters in length and form dense marine forests. Algae are found in the fossil record dating back to approximately 3 billion years in the Precambrian