SARS-Cov-2 is a virus. It's a small virus, about 30 nanometers big. It is RNA encased in a membrane covered with glycoproteins. It is easily spread, can cling to water droplets in the air for up to three hours, and can stay on surfaces for up to 72 hours. When in your body, it's main goal is to use your cells to reproduce itself, then to kill of the cell it used for reproduction.
SARS-Cov-2
COVID-19, or Coronavirus Disease 19, is caused by the virus SARS-Cov-2. The main symptoms it presents are fever, cough, and respiratory problems, like pneumonia. Other symptoms can present in more severe and emergent cases.
COVID-19
Coronavirus
Coronavirus is not the actual name of SARS-Cov-2 or COVID-19. Coronaviruses are actual a group of viruses that usually circulate in animals such as camels, bats, and cats, but often times they do mutate and infect humans. SARS-Cov-2 is one of these viruses. These viruses usually cause flu-like symptoms, but may have more dangerous symptoms in severe cases.
SARS
SARS, or Severe Acute Respiratory Syndrome, is also a type of coronavirus. An outbreak occurred in 2002, where it first developed in Southern China and spread to more than two dozen other countries. The symptoms are very similar to COVID-19 and severe cases can break into pneumonia. MERS is also a coronavirus that originated from camels. An outbreak first occurred in 2012 in Saudi Arabia and spread to 25 other countries. Symptoms were very similar to COVID-19.