Developing intelligent control of photoresponsive materials: from switch-type to multi-mode

> 2) functional states by varying light conditions. In this tutorial review, the light-switchable optical, electrical, chemical, mechanical and morphological properties of photoresponsive materials with switch-type control logic is introduced. The multi-mode control of photoresponsive materials is discussed from two aspects: (1) switching between multiple stationary states, termed as multi-stable control and (2) switching between multiple nonequilibrium states, termed as multi-stage control. The potential applications and future challenges are envisioned to encourage further and continuous developments for the multi-mode photoresponsive materials.