Zeno put forward a number of paradoxes. The upshot of many of them is that motion is impossible. This is a pretty startling conclusion, but his reasons seem fairly plausible.
Suppose I want to go out to eat and I decide to walk to the restaurant. Let A be my house and B be the restaurant. In order for me to get from A to B, I must cover half the distance between them. So I must get to point C. But in order for me to get from A to C, I must cover half of that distance. So I must get to point D. But in order for me to get from A to D, I must cover half of that distance. So I must get to point E... you get the idea. The issue is that there are an infinite number of "halves" that I have to traverse and so I'll never be able to get the full distance. How can one ever traverse an infinite number of points? So I can never actually get to the restaurant. Of course, we can generalize this and so it looks like all movement is impossible. So, contrary to the way things appear, nothing is really moving!
This wonderful clip explains another of Zeno's paradoxes (sometimes called "Achilles and the Tortoise") quite well. It has quite a bit in common with the one I describe above and the visual representation of the issue might be helpful.
Now, of course, most of think motion is possible. So the trick is identifying where Zeno's argument went awry.
Good luck and enjoy the weekend!