Nanoparticles have been used as antimicrobial and antiviral materials, especially, in advanced healthcare applications. This is due to their advanced physicochemical and biomedical (size and solubility) properties. Silver (Ag) is the first material used for several medical applications in human daily life. Mainly, Ag nanoparticles can generate influential active radicals, that can easily interact with bacterial envelopes and inhibit bacterial growth. In addition, they can be used against many viruses (including COVID-19) and also for the control of the virus spread and viral infections. This chapter addresses the importance of Ag and its derivative materials against several bacteria and viruses. In addition, we highlight, briefly, the reports on the recent articles.