What are two uses for vaccines?

The correct answer is: 1) to protect the individual from a disease, and 2) to protect the rest of the population because of herd immunity.

Explanation:

Vaccines are used to train the immune system for when it encounters a pathogen that can cause a disease. In order to achieve this, vaccines contain a weakened version of the pathogen - this way, the immune system remembers the previous encounter and now has an effective response prepared.

By vaccinating, not only you protect your own body, but you also protect the whole population. This phenomenon is called herd immunity and happens when the majority of the population is immune to an infection (because they vaccinated) and, therefore, they can now protect people who are not immune because of different conditions, like immunodeficiency or immunosuppression.