You set up accounts on your device to get access to information stored on the web.
You can use multiple Google™ accounts and Microsoft Exchange ActiveSync accounts on your phone.
When you add accounts, your contacts and calendar will be updated to add the information from that account. If you remove an account, any information you synced will be removed from your phone, but it is not deleted from your account.
To add an account:
Settings.Follow the instructions to enter information about the account.
Depending on the account type, you may be asked what kinds of data you want to sync. You can always change this later to control data usage.
To remove an account:
Settings.
> Remove account.global-en-us-en-us-3213-42