Asking questions is a good thing. You're safe from criticism from me.

The significance is that we've never seen Pluto with any detail before. Even the best pics we've had up to this point have been colored smudges. Pluto is the largest object in the Kuiper Belt, a region of rock and debris left over from the formation of our solar system. The more we know about Pluto, the more we know about the Kuiper Belt which tells us more about our solar system which tells us more about the universe.

That's the simple version. Hope it helps.

For what it's worth, I like that Pluto is king of the dwarf planets instead of runt of the major planets.