Scanning tunneling microscopy (STM) is a powerful imaging technique used to observe 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 become essential in nanotechnology and materials science. It enables scientists to study the properties of materials, manipulate individual atoms, and explore phenomena at the nanoscale, contributing significantly to advancements in various fields.