Ferroelectric materials with domains being the basic microstructures, have been investigated for about 100 years. With the development of the material fabrication method and the characterization technique, the important influence of domain configuration on the physical properties of ferroelectrics becomes more and more prominent. Recent researches even reveal that the domains and domain walls can act as individual functional units of micro-nano electronic devices, possessing wide potentials in the areas of information storage, energy transformation, electro-mechanical drive, quantum computation, etc. In this paper, starting from group theory analysis of domain structures, we introduce first the formation and the structures of ferroelectric domains, and then the macroscopic mechanical spectra as well as the electrical properties of the ferroelectric materials. Finally, the recent research progress of polarization switching and domain characterization by piezoresponse force microscopy are also reviewed.