Over the past 28 months, the induced pluripotent stem cells (iPS cells, with characteristics identical to those of embryonic stem cells (ES cells)) directly in vitro reprogrammed from nonembryonic cells and tissues have captured great attentions in both scientific community and general public. Somatic reprogramming, dedifferentiation and the resource of pluripotent stem cells become the research hot points of stem cells and developmental biology. Person-, patient- and disease-specific iPS cells could be very useful in regenerative medicine and drug discovery, etc. iPS cell history, the several key steps in generating iPS cells (including approaches to gene delivery, combined uses of defined factors and small molecules to induce somatic cells into iPS cells, and choice of somatic cell types), patient- and disease-specific iPS cells, in vivo and in vitro differentiation of iPS cells, and the possibility of genetic modification-free iPS cells were discussed.