In recent times, renewable energy resources have been greatly researched because of the increasing concern to minimize global warming and meet energy demands. Energy storage systems have become useful tools for sustainability and meeting energy needs. Solar energy has proven in recent times to be the primary and most prevalent option due to its environmental friendliness, availability, and minimal pollution. Effective utilization of available energy resources has led to developing new alternative energy devices like the solar thermal energy storage system (STESS) with a solar energy source. Solar thermal energy systems are efficient systems that utilize solar energy to produce thermal and electrical energy. This review aims to give a detailed overview of solar TESS, different TES application systems, and effective methods of increasing the system performance to provide energy during deficient times. The various classifications, basic components, the principle of operation, application areas of STESSs, prospects, and extensive reviews on these aspects have also been discussed in this review. The different factors to be considered geared towards meeting energy demands and increasing the efficiency of solar TES systems have been duly detailed. This review is a single manuscript with a detailed overview of STESS, the principle of operation and components of STESS, thermal energy storage materials, a description of different application systems, and a discussion of factors responsible for improving the system efficiency.