Scanning tunneling microscopy (STM) is a powerful imaging technique used to visualize surfaces at the atomic level. It works by scanning a sharp metal tip very close to a conductive surface, allowing electrons to "tunnel" between the tip and the surface. This tunneling current is measured to create detailed images of the surface's topography. Developed in the 1980s by Gerd Binnig and Heinrich Rohrer, STM has revolutionized the field of nanotechnology. It enables scientists to study the properties of materials, manipulate individual atoms, and explore the behavior of electrons in various substances, providing insights into fundamental physical and chemical processes.