Ans : Cloud computing is the delivery of computing as a service rather than a product,whereby shared resources, software, and information are provided to computers and otherdevices as a metered service over a network. Confused ? well, that was a wiki defination .
I will explain it to you in simple terms
Suppose if you have a single picture of your beloved boyfriend and you don’t want to lose it you canupload it to facebook .It will be there for ever .Or send it via your email and you can find it later in you sent items list .Now,did you need to provide your computer space for protecting it ?
No . So where did it go ? How do you retrieve when you log into your facebook account or gmailaccount where you have your pic ?
This is what we say is your picture is in cloud . So email ,document eg pdf files ppt and mp3 files all can be put on cloud .When you
need them you can acces them.when you upload it to any site from which you can retrieve it ,the picture or music file or video is stored on the computers which have huge storagespace .There may be a cluster of hard drives say .This is what we call data center .
Data centers are dispersed through out the world to provide quick access to the data from the nearest data center as the fetching time will be least from the nearest data center.
Yes there are many of them .
1) First is data loss . As in mentioned we can upload our data and keep it in the cloud.
2) Makes your life simpler .For instance
a) a simple dropbox application which can downloaded and signed up (i.e. you need to register for using it ) has a simple drag and drop functionality.So you can just upload drag and drop files to your dropbox folder and gradually it will sync it with your
dropbox account .Dropbox provides 2gb of free disk space .It needs internet connection to sync your data to your cloud
b) Amazon provides 5 GB of free cloud space .You can upload your files to its cloud drive which you can manage just like files and folders on your pc .
3) Another big advantage of cloud is that you can access data from any remote computer .So you need not carry data along with you.If say you want to listen your favourite song upload it to amazon cloud drive and you can play it from anywhere .(This facility is not supported in all countries so you will need to download your stuff in that case in order to play )
4) Using cloud saves a lot of your disk space and with the prices of hard disk drive at its pek you are always better off .You no longer need to keep all your files on your hard disk .Rather keep it on cloud and use it . This also provides for backup .
5) MOST IMPORTANT of all why the companies and enterprises are shifting to cloud is because of it INSTANT SCALABILITY .
Suppose you hosted an application on a server in earlier days ,you had to predetermine the approximate number of user to buy so much space and resources to ensure that your server doesn’t slow down when number of users increase .And in case you have lesser number of users that your expectations, all these days you had to pay for the services you you don’t require .
So with cloud computing you can get minimum resources and when the number of user increase beyond your expectation ,there is facility for instant scaling .For instance ,say you bought space for 10 user and when number of user reach say 9 you can instantly ask the service providers to scale .Like windows azure provides cloud services with 909 days trail.(They will ask your credit card details ,so don’t leave your applications running on the server after 90 days else you will be charged as per usage).
You can create your private cloud using ubuntu cloud enterprise for ubuntu 10.04/10.10 or ubuntu cloud infrastructure (for 11.10-Oneric ocelot).
6) Cloud computing improves your application’s performance .So traffic can be monitered and scaled which implies it will be COST EFFECTIVE for users .