• The human eye does not distinguish an object smaller than 0.02 mm.
• The first magnifying devices were glass lenses and water.
• When the microscope was invented, cell research began.
• Objects up to 200 nm (0.2 micrometer, 0.0002 mm) can be distinguished with the current light microscope.
• The electron microscope does not use visible light, instead using an electron beam. They can achieve millions of magnifications.
• Microscopy and nanotechnology are emerging fields of scientific technology.
• Key words: sample, magnification, microscope, lens.