Nano-engines are tiny machines designed at the nanoscale, typically measuring between 1 to 100 nanometers. They can convert energy into motion and are often made from materials like carbon nanotubes or DNA. These engines have potential applications in fields such as medicine, where they could deliver drugs directly to cells, or in electronics, where they might improve the efficiency of devices. Researchers are exploring various types of nano-engines, including molecular motors and nanobots. These innovations could lead to advancements in technology and healthcare, enabling precise control at the molecular level. As development continues, nano-engines may revolutionize how we approach complex problems in science and engineering.