This paper intends to introduce the beam dynamics in the cyclotron. The long history of the cyclotron evolution is reminded and the different developments since 1929 from E. Lawrence’s great idea are reviewed from conventional cyclotron to synchrocyclotron. The transverse and longitudinal beam dynamics are detailed as well as the specific quantities applied to cyclotron. Finally, and since the study of the dynamics in cyclotrons differs from the one in synchrotrons due to the non-periodic lattice, an opening to beam dynamics computation is proposed to handle the peculiar way of cyclotron tuning. A list of books, articles and proceedings is referred to the end to go deeper in the subjec
