Abstract: This minireview details the design, development, and demonstration of chemical strategies that are used to create molecular level devices and implement digital processing and communication. The design principle here is to integrate two informationally rich but relatively simple nanobuilding blocks with their complements through photoinduced electron transfer, redox processes, conformational changes, photoinduced energy and proton transfer, and supramolecular events into functional molecular devices. Depending on the abundant electrochemical properties of TTF, lots of D-A-D supramolecules and [2]rotaxanes with the different linkages were synthesized for studying photoinduced transient electron transfer and nanorecording abilities. Also detailed below are the methods to take advantage of the distinct abilities of electron, energy, and proton transfer of photochromic spiropyran to design supramolecular ensembles and control their absorption, fluorescence, and conductive properties by light and chemical reagents. Based on the spectral and electrochemical behaviors of these ensembles, a whole bunch of novel molecular switches, logic gates, and molecular circuits were constructed. At last, we present an interesting insight into designing a new type of luminescent spiropyan molecules with stable merocyanine open form in solution as well as in the solid state.