A lot of people think that JavaScript is a sort of simplified version or spin-off of Java. But in fact the similarity of the names is a coincidence, and the two are unrelated except that both are used to write computer programs that can run inside a web browser.
A vaccine is a medication, usually made from something that is or was alive, that gives immunity to a particular bacterial or viral disease. vaccine is a medication, usually made from something that is or was alive, that gives immunity to a particular bacterial or viral disease.
Flu vaccine is an inactivated vaccine, meaning that it contains killed influenza virus. The killed influenza virus is injected into muscles or skin and stimulates the immune system to produce an immune response (antibodies) to the influenza virus.