Coronaviruses are viruses that cause respiratory and/or enteric infections in humans and animals. They have specific requirements for infecting different species and tissues. These viruses have unique club-shaped spikes on their surface. There are three main subgroups of coronaviruses, each with different members like avian, mammalian, and unrelated types. The researchers studied the assembly of coronaviruses and found that they all belong to the same virus family, despite their differences in antigenic properties. This information helps us understand how coronaviruses infect and spread in different hosts.