BCCL
Basically, there are two types of vaccines: first, those developed on protein-based technique, and second, developed by gene-based technique/platform. Genetic platforms are more recent than the conventional protein-based techniques. A genetic material (nucleic acid) of the virus is used to produce proteins inside the cell in the former.
They are three types of vaccines:
a) Viral vector - where a harmless virus is used to carry a gene encoding the spike protein of SARS-CoV-2.
b) DNA - the gene encoding for spike protein is inserted in a bacterium that converts in the nucleus of a cell to mRNA and forms spike protein.