@AceHero : That's
exactly why they are round.
Every object that has mass, also has gravity. This has been proven here on Earth. The more mass something has, the more gravity it has. Gravity always comes from the center of the object in question.
If you take a huge flat disc, what is going to happen, is that gravity will override the strength of whatever the disc is made out of and the edges of it will curl in on each other and you will eventually end up with a ball because the force of gravity pulling the edges towards its center is greater than the resilience of the material the disc is made out of.
The Ball (or sphere) is the only geometric shape known to Man that can sustain itself no matter what size/mass it is, in fact the bigger it is, the more perfect round it tends to be because it has more gravity and thus everything in and on this object is pushed towards making a perfect sphere.
And there's also the fact that anybody can grab a telescope, take it apart to make sure there's no government conspiracy cameras and other such things in there, put it back together, take it out and look up into space at night, and see that
every single object in space is round except for maybe smaller asteroids (most of those seem to be vaguely round, egg-shaped, etc).
How would a huge flat disc sustain itself, but yet have Gravity? Why would it be the one-and-only object in the entire universe that is different than everything else?
Again, Flat Earth just keeps raising more questions and problems against itself while Round Earth keeps answering all of these, and doing so quite easily.
EDIT: I'll also note that
@morse86 still hasn't explained how/why we have the Equator and the alternating seasons of the Northern and Southern Hemisphere, things we've observed, documented, and predicted with pinpoint accuracy. The "Sun is close and rotates above the earth like babies' toys above a crib" doesn't work to explain what we actually see in practice on Earth today.
In fact, Round Earth people have constructed many models that are down to the very day in specifics and they match, meanwhile, Flat Earth people throw up an image or two... but they don't tell you where the Sun/Moon is in each day of the year to explain how exactly seasons work in their model, nor do they explain how you see what you see in the sky at various parts of the year.