What I call stereo microscopes (sometimes called dissecting microscopes) are low power instruments that look at opaque objects (such as mineral crystals, flowers, and insects). They typically offer magnifications of 10-30 and often offer a continuous "zoom" to change power. I use one of these more than any other, and find them more pleasant and useful than a biological microscope.
What I call "biological microscopes" are what most people think of when they think of a microscope. They look at slides using transmitted light. They generally offer several magnifications by changing objectives by means of a rotating turret. The commonly offered magnifications are 100, 400, and 1000. The 100x objective that gives the 1000 magnification is generally an oil immersion objective.
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