Silica aerogels have gained significant attention due to their unique properties, such as being the lightest solid material, having small pore sizes, high porosity, and ultralow thermal conductivity. Advances in synthesis methods have enabled the creation of silica aerogel-based composites with different materials, combining the properties of silica with other materials to create reinforced architectures with valuable applications in various fields. This paper provides an updated overview of silica aerogels, covering their preparation methods, properties, composites, and applications. The synthesis of silica aerogels involves gel preparation, aging, and drying techniques, with supercritical drying being the most common method. The properties of silica aerogels include a unique pore structure, low density, ultralow thermal conductivity, hydrophobicity, optical transparency, and mechanical properties. Composite materials containing silica aerogel have been developed for biomedical, environmental, and construction applications, showing enhanced performance in areas such as insulation, sound insulation, and drug delivery. Despite their advantages, silica aerogels face challenges such as fragility, high processing costs, and environmental concerns. Future research should focus on optimizing synthesis methods, improving mechanical properties, and exploring new applications to address these challenges.Silica aerogels have gained significant attention due to their unique properties, such as being the lightest solid material, having small pore sizes, high porosity, and ultralow thermal conductivity. Advances in synthesis methods have enabled the creation of silica aerogel-based composites with different materials, combining the properties of silica with other materials to create reinforced architectures with valuable applications in various fields. This paper provides an updated overview of silica aerogels, covering their preparation methods, properties, composites, and applications. The synthesis of silica aerogels involves gel preparation, aging, and drying techniques, with supercritical drying being the most common method. The properties of silica aerogels include a unique pore structure, low density, ultralow thermal conductivity, hydrophobicity, optical transparency, and mechanical properties. Composite materials containing silica aerogel have been developed for biomedical, environmental, and construction applications, showing enhanced performance in areas such as insulation, sound insulation, and drug delivery. Despite their advantages, silica aerogels face challenges such as fragility, high processing costs, and environmental concerns. Future research should focus on optimizing synthesis methods, improving mechanical properties, and exploring new applications to address these challenges.