Diatom biosilica is a valuable element for modern age application like in the field of nanotechnology. But we cannot get nano-structured biosilica commercially until we explore the diatom biology, its genomics and proteomics. This book illustrates briefly about biosilica, diatom biology, its cell wall morphogenesis, biosilica formation, diatom genomics and proteomics and the uses of diatom biosilica. Though the use of diatom biosilica will be in nanotechnology, the exploitation of diatom biosilica formation can only be done by any zoologist or any marine microbiologist. This biosilica has the enormous capacity to revolutionize our whole system of the world. It can be used in a diversified ways like in toxic gas detection, drug delivery, bio-capsule etc. This book is mainly helpful for graduate students, marine microbiologists and zoologists working in field of diatom. It will also help the students of nanotechnology those who are studying about diatom's nano-patterned biosilica and its application.