SARS is a new type of infectious pneumonia that emerged in China in November 2002. It spread around the world through an outbreak in Hong Kong in March 2003. Patients were reported in 29 countries, and around 800 people died, although a majority of these cases were in Asian countries. Within a month after the virus that causes SARS was isolated, its entire genome sequence became available. The result is the acknowledgement of a novel coronavirus, now called SARS coronavirus (SCoV), that is different from other already known existing human and animal coronaviruses. Since a number of scientists from distinct fields have participated in the research on this emerging virus, a plenty of information has become available, and now SARS-CoV has become one of the best-studied members among coronaviruses. In this review, I would like describe on SCoV virology by comparison with other well-studied coronaviruses. It covers the taxonomy, structure of virion, viral genome and proteins, unique replication strategy, receptors and viral pathogenesis. In the last part, I mention with my personal speculation about the origin and evolution of SCoV.