What is an e-mail profile?

E-mail profiles are what Outlook uses to remember which e-mail accounts you use and where the data for each account is stored. Each profile provides Outlook Support with the following information:
What account information to use This information includes the user name, display name, e-mail server name, and Internet service provider (ISP) (ISP: A business that provides access to the Internet for such things as electronic mail, chat rooms, or use of the World Wide Web. Some ISPs are multinational, offering access in many locations, while others are limited to a specific region.) account password.
Where the e-mail data is delivered and stored In Outlook, data is delivered and stored either on the e-mail server or a in .pst file on your computer. This data includes rules, messages, contacts, calendars, notes, tasks, journals, Search Folders, and other settings.
Outlook e-mail profiles are stored in the Windows registry. When Outlook starts, it retrieves the profile information from the registry.
You use the Mail icon in Control Panel to access options for configuring Outlook e-mail profiles. The Mail icon won't appear unless you have Outlook installed and have run the program at least one time.
When you run Outlook for the first time, a startup wizard guides you through the process of creating a new profile. The profile thus created runs whenever you start Outlook. Most people maintain only one profile — however, you might sometimes find it useful to have more than one. For example, you might want to use one profile for work mail and a second profile for personal mail. Also, if other people use the same computer that you do, their accounts and settings can be kept in separate profiles that have different names.
You cannot use passwords to protect Outlook profiles. To help protect your Outlook data from intrusion by other people, you should use a password-protected Windows user account.
You cannot switch from one e-mail profile to another while Outlook is running.
A basic profile consists of one or more e-mail accounts and a storage file. A private individual might have an Internet e-mail account, such as a POP3 account, while corporate workers might have a Microsoft Exchange account. Accounts of other types (including IMAP4 and HTTP accounts) can be added to any profile, and so can additional storage files (such as an Archive.pst file for keeping older messages). Sometimes extra services, such as fax and address book directories, may be included as well.
While a profile can include multiple Internet-type accounts, it can include only one Exchange account.