Used in electronics for reliable, corrosion-resistant connections in connectors, switches, and printed circuit boards. Common in jewelry and decorative items due to its lustrous appearance and resistance to tarnish. Applied in dentistry for crowns and bridges because of biocompatibility and durability. Utilized in aerospace for coating components to reflect infrared radiation and prevent overheating. Employed in medicine, particularly in treatments for rheumatoid arthritis and in some cancer therapies. Serves as a catalyst in chemical reactions, especially in processes involving oxidation and environmental cleanup. Used in nanotechnology, where gold nanoparticles aid in medical imaging, drug delivery, and biosensors.