Neutral Atoms in the Solar Corona

The presence of neutral atoms in the million degree solar corona is remarkable in itself, but even at that temperature one expects that 0.3 out of a million H atoms will be neutral. Neutral He is even more rare, but it has been detected. In spite of their small numbers, neutrals can be valuable diagnostics for the electron and proton temperatures, the density and the outflow speed in the corona. We discuss the injection of neutrals by CMEs, jets, comets, collisions with dust grains and the interstellar wind, along with the coupling to protons neutrals, and we consider some of the results from the diagnostics.