Hi all,
The distinction is between CRT monitors and LCD monitors. CRT are the big monitors. The new ones have a flat screen, not a curved one, which makes them really swell monitors. This is what Witchen bought, I believe, and a 21 incher too! When I got a new monitor, I thought about sizing up, but I could not even get my 19 inch monitor (18 inch viewable) up the stairs by myself. I could move it around, it's not that heavy, but for the stairs part I needed help. That's the disadvantage, the monitors are big and heavy. LCD are those thin monitors. The confusion is that CRT monitors can now have a flat screen.
From all I've read, LCD monitors are catching up, but CRT are still said to be best for gaming. For LCD monitors the problem is the refresh rate (how fast the screen repaints itself), also some other problems. Some LCD monitors are better for gaming than others. Tom's hardware periodically does reviews -
http://www.tomshardware.com/ . He also has good (non jargon) explanations of stuff. If you are a serious gamer, especially action games, you proabably want to check out Tom's reviews of CRT and LCD monitors.
For all I've said about CRT monitors being better for gaming, everyone's experience and needs are different. If you don't play a lot of action games, perhaps an LCD monitor would be fine for you, and there are people on this thread who say they like them.