Since its discovery in 1891, the pneumococcus has been one of the most extensively studied microbes, and was involved in several historical findings such as the discovery of genetic material that was later shown to be DNA. The pneumococcus is part of the normal bacterial flora of the nasopharynx, but can on occasions progress to sterile sites of the body and cause invasive diseases. There are about one million new invasive pneumococcal infections every year, majority of which occur in the developing world where children <5 years are most affected. The burden of pneumococcal disease is further heightened by the increasing prevalence of multidrug resistance of the organism. The pneumococcus remains a pathogen of immense public health significance and understanding its biology, particularly the pathogenesis and antibiotic resistance is crucial to controlling pneumococcal disease.