  As the heaviest known fundamental particle, the top quark has taken a central
role in the study of fundamental interactions. The top quark mass is a
fundamental parameter of the standard model which places constraints on the
Higgs boson mass and electroweak symmetry breaking. Observations of the
relative rates and kinematics of top quark final states may provide constraints
for new physics processes. Past and current experimental measurements are
presented with a critical view, and a look at the future prospects.
