Well okay, my introduction on this page wasn't very helpful. Some insects have five eyes while most don't have that many. What makes it a bit confusing is that insects have two types of eyes: compound eyes and simple eyes. Some have one type, and some have both types of eyes.

If you look at the photo of the fly below you can see the really big compound eyes on either side of its head. Each of those compound eyes is a cluster of lots of individual lenses. With all of those lenses working together they would give the fly an ability to see in almost every direction at once.

The compound eyes on
this fly are easily seen

Scientists believe those compound eyes would provide the fly a crisp, detailed view of the things nearby. However, they also believe that as things get further away from the fly, they would become less clearly seen. So the idea is that those compound eyes give sharp images of things up close and blurred vision of things in the distance.

In the blow-up detail taken from the photo below you can see the big compound eyes. I used that shot because it clearly shows the surface of those eyes dotted with all those individual lenses.

And in between those two compound eyes is a triangular formation of simple eyes. Insects can have as many as three simple eyes, like this fly does. The simple eyes are not so good at detail but they help the fly see movement.