I hav seen lots of web host offring unmetered space,bandwidth so can anyone tell me the meaning of unmetered space,bandwidth?
Unmetered means they do not have a fixed amount of disk space or bandwidth that you can use. Normally you choose a plan of say 750MB disk and 20GB bandwidth then once you reach 750MB of disk you have to buy more space or once you exceed 20GB used bandwidth you have to your account suspended or pay an overage fee. However the resources will be capped in another way as there's no such thing as a free lunch. You may have unmtered bandwidth on a dedicated server but it may be capped at 10Mbps or about 3TB per month, could be slower, could be faster and shared. They may say unmetered disk but then limit the number of inodes you can use, or the number of files you can store. They may limit the amount of CPU. There's lots of ways to limit resource usage so read the small print. If you come across a host offering unlimited simply move to the next as unlimited is not possible.
Unlimited doesnt really exist, its just a way to attract customers, most of those offers are for shared hosting accounts, servers working in a cluster mode. But they limit you with things in their terms such as not been able to serve videos or having it as a file server, because as soon as they notice that a lot of people start download a file from your hosting account then they will block you. Really depends what your website is all about. As for unlimited space, well no one really uses that amount of space, unless you are a high profiled multimedia company. But then again restrictions such as serving media files are not allowed. And forget about serving anything illegal such as warez or cracks or any of that type of thing.
Unlimited = Is like not being limited for the speed of your car but for the engine's power. So if you use more than 15 % of your engine's power will be out of the game. It's a trick to make you believe you have no limitations when in fact you can't drive with more than 50km / h before breaking the 15 % engine power rule. Unmetered = They don't count your bandwidth and storage directly, but "unmetered" can also be "unmetered up to ... only they know"... When a store next to you will sell "unlimited" and "unmetered" food for few 5 $ / month only then to believe them.