Microscopes are currently used in a variety of disciplines, fields and contexts. For example, biologists use microscopes to study tiny organisms, such as bacteria and algae. Doctors and lab workers often use microscopes to investigate biological samples for parasites.
Because of advances in microscope technology, modern scientists are able to observe a number of small objects and phenomena. For instance, doctors can witness the transmission of nerve impulses in a sample of brain cells. Doctors can even watch cells producing their products, such as when a pancreas cell secretes insulin.
Microscopes are also used to examine the fine details of objects that are large enough to see with the naked eye. Crime investigators, for example, use microscopes to study the evidence they collect. For example, by viewing hairs at high magnification, investigators can determine whether hair was forcibly extracted or fell out on its own.
In addition to using conventional, light-based microscopes, many scientists use electron microscopes to investigate objects that are too small to be seen otherwise. Electron microscopes do not rely on a light source for viewing. They bounce a beam of electrons off of objects to determine their shape, rather than rays of light. Electron microscopes are necessary to visualize objects such as viruses.