Historians will probably never know who invented the first microscope, but the compound microscope is a more recent innovation. It is integral to laboratories, doctors, and scientists and has been in use for hundreds of years.
Compound microscopes use multiple lenses to increase magnification over single lens microscopes. In fact, most microscopes you'll see or use are compound microscopes.
The identity of the inventor of the compound microscope is debatable. The first compound microscope might have been built by a Dutch father and son in the 1590s. Galileo also developed a compound microscope.
Some types of compound microscopes feature binocular eyepieces (for two eyes), but some even feature three eyepieces. The third is for a camera.
An observer looking through a microscope is not seeing the specimen fixed at the bottom of the microscope. The observer is seeing an image that is projected by the microscope's lenses to a location just below the microscope's eyepiece.