A microscope is a laboratory instrument used to examine objects that are too small to be seen by the naked eye. Microscopy is the science of investigating small objects and structures using a microscope. The most common type of microscope is the optical microscope, which uses lenses to refract visible light that passed through a thinly sectioned sample to produce an observable image. Other major types of microscopes include the fluorescence microscope, electron microscope (both the transmission electron microscope and the scanning electron microscope), and various types of scanning probe microscopes. The magnifying power of a microscope is an expression of the number of times the object being examined appears to be enlarged and is a dimensionless ratio. The resolution of a microscope is a measure of the smallest detail of the object that can be observed. The primary function of a microscope is to study biological specimens, and it solely functions on two concepts – magnification and resolution. Magnification is simply the ability of the microscope to enlarge the image, whereas resolution should render high-quality details of the desired specimen in order to proceed with the experiment and analysis. Light microscopy is a general term used for any type of microscopy where light is being transmitted from a source which is on the opposite side of the sample, to the objective lens.