The article provides an overview of the properties and applications of room-temperature ionic liquids (RTILs) at electrified interfaces (EIs). RTILs are characterized by high charge density, electrochemical stability, low volatility, and tunable polarity, making them attractive for various electrochemical applications. The authors discuss the unique properties of RTILs, such as their non-uniform molecular charge density and the absence of a solvent in the pure RTIL electrolyte. They highlight the importance of understanding the electrical double layer (EDL) behavior in RTILs, which is crucial for applications like supercapacitors, electroactuators, and electrode kinetics. The article covers the thermophysical, transport, dielectric, and electrochemical properties of RTILs, emphasizing the challenges in predicting and modeling these properties. It also reviews experimental studies and simulations of RTILs at EIs, including the dynamics of EDL charging and discharging, and the impact of impeded dynamics on power delivery. The authors conclude by discussing the potential of RTILs in confined geometries, such as nanopores, and their applications in energy storage devices, batteries, fuel cells, solar cells, and flexible electronics.The article provides an overview of the properties and applications of room-temperature ionic liquids (RTILs) at electrified interfaces (EIs). RTILs are characterized by high charge density, electrochemical stability, low volatility, and tunable polarity, making them attractive for various electrochemical applications. The authors discuss the unique properties of RTILs, such as their non-uniform molecular charge density and the absence of a solvent in the pure RTIL electrolyte. They highlight the importance of understanding the electrical double layer (EDL) behavior in RTILs, which is crucial for applications like supercapacitors, electroactuators, and electrode kinetics. The article covers the thermophysical, transport, dielectric, and electrochemical properties of RTILs, emphasizing the challenges in predicting and modeling these properties. It also reviews experimental studies and simulations of RTILs at EIs, including the dynamics of EDL charging and discharging, and the impact of impeded dynamics on power delivery. The authors conclude by discussing the potential of RTILs in confined geometries, such as nanopores, and their applications in energy storage devices, batteries, fuel cells, solar cells, and flexible electronics.