The physical principles underlying the focused-image holography are considered. An analysis is given of the processes involved in holographic recording of focused images and of their reconstruction by illumination of a hologram with light of different spectral compositions, including white light. The problem of the depth of a scene, which is reconstructed satisfactorily by white light illumination, is discussed. The special features of the recording of focused-image holograms are considered in the case when the reference wave is complex. The quality of the reconstructed image is independent of the dimensions and shape of the reference source and the reasons for this are discussed. Conditions are given for the observation of reconstructed images using reference and reconstructing waves of different forms and spectral compositions. The principles and new applications of holographic focused-image interferometry are considered.