Cyanobacteria, the ancient photoautotrophs on the Earth have always been regarded as the most important organism to sustain life in the planet. They are among the first pioneering communities on various harsh habitat, hydrarch or xerarch, which finally facilitate the emergence of vast communities including higher plants. Being the progenitor of chloroplast, the cyanobacterial metabolisms has always fascinated microbiologist. Additionally, the ability of these prokaryotes to produce valuable and prolific sources of natural products signified their role in array of industrial sectors. Further, the attempts to engineer the cyanobacterial metabolisms in way to enhance production of these metabolites are gradually increasing. Therefore, in this book, we proposed to accumulate the knowledge of cyanobacterial metabolisms and molecules as an asset for students, researchers, and biotechnologists. Cyanobacteria: Metabolisms to Molecules will cover diversity, fundamental metabolisms, crucial metabolities and their synthesis, and bioinformatics.