III detector. CLEO-c studied the lower mass ψ states. CLEO and CUSB published their first papers back-to-back, reporting observation of the first three Υ states. Earlier claims of the Υ(3S) relied on fits of one peak with three components; CLEO and CUSB's observation of three well separated peaks dispelled any remaining doubt about the existence of the Υ(3S). The Υ(4S) was discovered shortly after by CLEO and CUSB and was interpreted as decaying to B mesons because of its large decay width. An excess of electrons and muons at the Υ(4S) demonstrated the existence of weak decays and confirmed the interpretation of the Υ(4S) decaying to B mesons. CLEO and CUSB later reported the existence of the Υ(5S) and Υ(6S) states. CLEO I through CLEO II had significant competition in Υ physics, primarily from the CUSB, Crystal Ball and ARGUS experiments. CLEO was able, however, to observe a number of Υ(1S) decays: τ+τ−, J/Ψ X and γ X with X = π+, π0, 2π+, π+K+, π+p, 2K+, 3π+, 2π+K+, and 2π+p. The radiative decays are sensitive to the production of glueballs. CLEO collected more data at the Υ(1-3S) resonances at the end of the CLEO III era. CLEO III discovered the Υ(1D) state, the χb1,2(2P)→ωΥ(1S) transitions, and Υ(3S)→τ+τ− decays among others. CLEO-c measured many of the properties of the charmonium states. Highlights include confirmation of ηc', confirmation of Y(4260), pseudoscalar-vector decays of ψ(2S), ψ(2S)→J/ψ decays, observation of thirteen new hadronic decays of ψ(2S), observation of hc(1P1), and measurement of the mass and branching fractions of η in ψ(2S)→J/ψ decay. Tau leptons CLEO discovered six decay modes of the τ: τ → K−π0ντ, e−ντeγ, π−π−π+η ντ, π−π0π0η ντ, f1π ντ, K−η ντ and K−ωντ. CLEO measured the lifetime of the τ three times with a precision comparable or better than any other measurements at the time. CLEO also measured the mass of the τ twice. CLEO set limits on the mass of ντ several times, although the CLEO limit was never the most stringent one. CLEO's measurements of the Michel parameters were the most precise for their time, many by a substantial margin. Other measurements CLEO has studied two-photon physics, where both an electron and positron radiate a photon. The two photons interact to produce either a vector meson or hadron-antihadron pairs. CLEO published measurements of both the vector meson process and the hadron-antihadron process. CLEO performed an energy scan for