The 'Little Neutral One': an overview of the neutrino

Recent evidence for neutrino oscillations implies that at least one neutrin o species has a non-vanishing mass. In this historical review of theoretica l and experimental interest in these particles, we emphasize the role South Africa and South Africans played in the first detection of naturally occur ring neutrinos in 1965. We also chart the history of the neutrino from its unorthodox postulation in the 1930s to its contemporary role in astrophysic s and elementary particle physics.