Stereo microscopes are branched out from other light microscopes for the application of viewing “3D” objects. These include substantial specimens, such as insects, feathers, leaves, rocks, sand grains, gems, coins, and stamps, etc. Functionally, a stereo microscope is like a powerful magnifying glass. Unlike a compound microscope that offers a flat image, stereo microscopes give the viewer a 3-dimensional image that you can see the texture of a larger specimen. 

Unlike a compound microscope that can only see a very thin specimen, stereo microscopes can be used for viewing almost anything you can fit under them. However, stereo microscopes offer lower magnification, typically 2.5x-50x, comparing to compound microscopes.