Molecular tests, like the PCR or Polymerase Chain Reaction Test, are designed to test for evidence of the viral genetic material present in your body. The best option currently available is a nasal swab PCR test, as they are incredibly sensitive, making it easier for them to detect accurately whether you have coronavirus or not.
Antigen Tests, as the name suggests, are designed to tell if there are coronavirus antigens, a special type of proteins, present in your body. These work in a similar way to at-home pregnancy test kits, which are also antigen tests.
These deliver quicker results and are less expensive. However, although Antigen Tests have been known to be very accurate at producing positive results of viral antigens in your body, you may still need to have a molecular test to get a more conclusive result as Antigen Tests have been known to produce a higher rate of false-negative results.