Recent progress in photoelectron holography with atoms and molecules in strong laser fields is reviewed. From a semi-classical model, four kinds of holography patterns are predicted, which include two forward rescattering interference patterns and two backward rescattering patterns involving subcycle interference of electron dynamics. One of the forward rescattering patterns has been experimentally demonstrated with mid-infrared free-electron lasers. The other three interference patterns are obtained from numerical simulations by solving the time-dependent Schrödinger equations for symmetric and nonsymmetric molecular ions in ultrashort intense lasers. It is shown that photoelectron holography is a new tool for attosecond-resolved imaging of molecular structure.