Please note that the content of this book primarily consists of articles available from Wikipedia or other free sources online. Coronaviruses are species in the genera of virus belonging to the subfamily Coronavirinae in the family Coronaviridae. The name "coronavirus" is derived from the Latin „corona“, meaning crown or halo, and refers to the characteristic appearance of virions under electron microscopy with a fringe of large, bulbous surface projections creating an image reminiscent of the solar corona. Coronaviruses primarily infect the upper respiratory and gastrointestinal tract of mammals and birds. Four to five different currently known strains of coronaviruses infect humans. The most publicized human coronavirus, SARS-CoV which causes SARS, has a unique pathogenesis because it causes both upper and lower respiratory tract infections and can also cause gastroenteritis. Coronaviruses are believed to cause a significant percentage of all common colds in human adults. Learn more about coronaviruses, their life-cycle and transmission, as well as symptoms and cures of the deadly diseases they cause in this book.