The paper gives a review on progresses in the past four decades in bipartition model studies. Its basic ideas and concepts, main mathematical formulae and numerical methods, and its relevant applications are described. The model has been extended from a transport theory for electrons of medium energy range to a unified and accurate transport theory of charged particles, covering ion transport, atomic cascade collision, particle emissions in surface sputtering, and penetration of electrons of radiation therapy energy range. The 15 figures give an extensive comparison between the results given by using the bipartition model and the data taken from other theories and experimental measurements, which shows that the bipartition model is an accurate, powerful and unified transport theory of charged particles. Problems remaining to be solved with the bipartition model are discussed in the paper.