Evolution of rotation on the main sequence as a function of the central mass fraction of hydrogen for all the stellar models from 1.7 to 120 M_⊙. Left: evolution of the equatorial velocity. The curve for the 1.7 M_⊙ is the bottom line at the beginning of the evolution (X_c = 0.72), and that for the 120 M_⊙ the upper line (increasing equatorial velocity for increasing mass). Right: evolution of the υ_eq/υ_crit ratio. The curve for the 1.7 M_⊙ is the upper line during the MS, and that for the 120 M_⊙ the bottom line during the MS (decreasing velocity ratio for increasing mass).