Molecular, antigenic, serological tests. Briefly, what is the difference?

We have been hearing a lot about the different tests available to promptly detect SARS-CoV2 infection. How are they different? A molecular test can be performed on a oro- or naso- pharyngeal swab or on a saliva sample and works by identifying the viral genome, namely the RNA of the virus. The RNA is identified by means of a PCR-based analysis. An antigenic test identifies directly the viral proteins (meaning the product of the viral RNA). It is usually performed on swabs. Antigenic tests on saliva samples are being developed. A serological test identifies the anti-SARS-CoV2 specific antibodies in the blood, produced by the body in response to either virus infection or vaccination.