I read few discussions and they were about anti-gravity (something about lifters).
But what is gravitation exactly?
"That species of attraction or force by which all bodies or particles of matter in the universe tend toward each other" was the definition I found on web.

My perception of gravitation is somewhat different, so correct me if I'm wrong.
It is as following:
First, there is space. I don't think what is so called "vacuum" is really empty.
But just least densed, and filled with some particles evenly. For simplicity, think of
mass in shape of a sphere with even density. When a mass is presented in the
space, it will be hit by some of particles and rest just pass through the mass,
depending on the volume and density. Because, it will be hit evenly from all
direction, it will stay at the same location. However, when two masses exist,
that "being hit evenly by the particles" gets disrupted, resulting less number
of particles on the line of the two masses. Then two masses are pushed toward
each other, not that they attract or pull each other. So I just wanted to say that
gravitation is not pulling, but pushing force. And I don't think anti-gravity exist.

Well, physics is not my major, and I'm too lazy to read or won't understand those articles filled with half of the words I never seen before. When someone reply to
this, please try to put words simple and plain.

Nobody really knows what gravity actually is. Currently physists believe gravity has something to do with the warping of the space-time fabric. At least thats what Einstein proposed. It seems to make more sense than what Newton had proposed first. But Einstein might not be right either. Physists are now trying too figure out if Gravity somehow embodies tiny little massless particles called gravitons. But we most likely wont know forsure if these gravitons are really exist until the Large Hadron Collider is finished being built in 2007.

Anti-gravity most definately exists, its been seen to have existed in several labrotories. (by the way, lifters dont create antigravity, they create an ion wind)

IF your to lazy to read stuff, watch these video clips, theyll explain gravity a bit
-Newton's Embarrasing Secret
-A New picture of Gravity
http://www.pbs.org/wgbh/nova/elegant/program.html

Heres a link on Antigravity
http://www.newscientist.com/news/news.jsp?...p?id=ns99992611

Thanks for the reply.
I checked the links, too bad I couldn't see those videos, not sure if it's my computer
or the site. Well, I have heard the word "graviton" and that two masses exchange
gravitons.
You said none really knows what gravity is but anti-gravity exists?
Just because some force is in reverse direction of gravity, calling that force
anti-gravity seems to be not right, or at least that's how I feel.
If you throw a ball upward, will you call that physical force anti-gravity too?

I didn't see comment of my perception of gravity. Maybe I didn't describe
well enough or is it just too stupid. In case of bad description, simplest picture
of my perception is that think of some case that winds blow from all directions, if
you put two balloons there, they will move toward each other cuz block the wind
in the line they form. Well, please try to put some comment on my perception
when writing reply.

I saw something about they will check the speed of gravitational force whether
if the gravity and light has same speed, and if they do not, Einstein's general
theory of relativity is wrong. I hope it's wrong cuz I think gravity is faster than
light.

It seems to me I saw a study that light is still considered faster than gravity. They theorized that if the sun were to somehow just disappear the planets would continue their orbits for about 8 minutes before just continuing on their merry way in a staight line. I read their theory and it seemed sound at the time 'cause I too thought gravity might be instantaneous. Wish I could remember more so I could relay it accurately.