Question

Can microorganisms be seen through naked eye? If not, how can they be seen?

Answer 1

Microorganisms are very small organisms and their members are spread across every kingdom of the living organisms as classified by Whittaker. Bacteria, fungi, protozoa, viruses, microalgae, animal larvae, rotifers etc. are all microorganisms. They may be associated with various economical benefits and can even be harmful by causing diseases, spoilage and deterioration. They have a wide range of nutritional habits from being photosynthetic, chemosynthetic, or heterotrophic (Parasitic, saprophytic etc.).

Complete answer:
Microorganisms cannot be seen through naked eyes due to their very small size.
Microorganisms are often viewed with the help of microscopic technique which uses a microscope to magnify objects of microscopic range such that they are visible and can be characterized.
Microscopy is a technique of examination of the structure of microscopic scale between micrometers ($\mu m$) and angstrom units (${\AA}$).
Microscopy is done with the help of a Microscope which is an instrument used to investigate structures of microscopic range. Now-a-days, Microscopy has become more advanced to view structures of even sub-microscopic and ultramicroscopic range.
The ability of the microscope is now-a-days utilized in the diagnosis of various diseases as their causal organisms are identified by visualizing them under the microscope.

Note:
A microscope is a device that magnifies things that would otherwise be too tiny to view, resulting in a picture that makes the object look larger. The majority of cell photos are taken with a microscope, and these images are referred to as micrographs. Magnifying glasses, on the other hand, contain just one lens and are referred to as simple microscopes, whereas compound microscopes have several lenses.