The paper by D.I. Khomskii provides an overview of multiferroics, materials that exhibit both ferromagnetic and ferroelectric properties, often along with ferroelastic behavior. The author discusses the microscopic factors that determine the coexistence of these properties and explores various routes to combine them in a single material. Key topics include the role of d-state occupation in transition metal perovskites, the significance of spiral magnetic structures, and a novel mechanism of ferroelectricity in magnetic systems due to site-centered and bond-centered charge ordering. The paper also delves into specific materials, such as magnetite (Fe3O4), and highlights the potential applications of multiferroics, such as controlling magnetic memory by electric fields. The author emphasizes the importance of understanding the coupling between different degrees of freedom in multiferroic systems and the need for detailed group symmetry analysis. The paper concludes with a discussion on the potential for discovering new multiferroic materials with interesting properties, particularly those with helicoidal magnetic structures.The paper by D.I. Khomskii provides an overview of multiferroics, materials that exhibit both ferromagnetic and ferroelectric properties, often along with ferroelastic behavior. The author discusses the microscopic factors that determine the coexistence of these properties and explores various routes to combine them in a single material. Key topics include the role of d-state occupation in transition metal perovskites, the significance of spiral magnetic structures, and a novel mechanism of ferroelectricity in magnetic systems due to site-centered and bond-centered charge ordering. The paper also delves into specific materials, such as magnetite (Fe3O4), and highlights the potential applications of multiferroics, such as controlling magnetic memory by electric fields. The author emphasizes the importance of understanding the coupling between different degrees of freedom in multiferroic systems and the need for detailed group symmetry analysis. The paper concludes with a discussion on the potential for discovering new multiferroic materials with interesting properties, particularly those with helicoidal magnetic structures.