Microscopes

Light microscopes are highly important in Biology because they allow you to see the smallest things like cells.

First lets start with the base, which connects to the arm, then there's the "Stage" which is where we put our objects on to examine them. 
Usually there's 3 objective lenses, with different magnification strengths, then there's the lens at the top which is where our eye goes and has a fixed magnification, then the tube which goes from the lens at the top to the lenses at the objective lenses,
then the coarse and fine focusing nobs to focus the lenses on the object on stage.  

Let's get this straight, there are two things that are important when looking through the magnifying glass (there's more but that doesn't matter right now), mainly the "image" and the "object".
When referring to the object you are usually referring to the object or sample you are looking at on the stage. So if we have let's say onion cells on the stage, that would be considered to be the "object" or "sample". 

The term "Image" comes from the image that we see when we look down, we see the individual cells, and what we see in the lens is the image. 

Light Microscopes work by shining or reflecting light onto the subject.
Or by using an adjustable mirror below the stage or by turning on a lamp at the bottom to illuminate the clear stage. 

First, the light shoots up towards and through the sample, then through the objective lenses, then through the tube then into the lens where our eyes are.
This, in turn, is necessary for the light to bounce off objects for our eyes to see, magnification happens when you magnify the object, so an x100 magnification means the object is magnified 100 times. 

Resolution means how detailed the image is, so if an object has a terrible resolution it is very blurry, while a good resolution is good when it is crystal clear and very sharp.