Name the instrument (or device) which is needed to see microorganisms.

A microscope is the essential instrument used to observe microorganisms, which are too small to be seen with the naked eye. The most commonly used type is the compound light microscope, which uses multiple lenses and light to magnify tiny organisms up to 1000-2000 times their actual size. For viewing extremely small microbes like viruses, scientists use electron microscopes that can magnify specimens up to millions of times. Anton van Leeuwenhoek invented the first practical microscope in the 17th century, opening up the invisible world of microorganisms to scientific study. Modern microscopes have advanced features like digital imaging and fluorescence capabilities. In educational settings, basic light microscopes allow students to observe bacteria, protozoa, fungi, and algae, making microbiology accessible and fascinating.