Outlook Web Access (OWA) from Microsoft Office 365 provides the ability for you to check your enterprise Exchange e-mail, using nothing more than a web browser. Instead of using Outlook on your local computer, you simply browse to a web address and then log in and check your e-mail.
The experience is very similar to other web e-mail services, such as Google’s Gmail or Microsoft’s Hotmail. What’s exciting about OWA, however, is that you finally get access to your enterprise e-mail, calendar, and contacts from any computer with an Internet connection and a web browser.
Outlook and Exchange are both e-mail-related products, but one is for users and the other is server software. Exchange is a server product that sits on a server in a data center and manages all your e-mail. Outlook is an application that you install on your local desktop and then use to connect to the Exchange server to check and manage your e-mail, contacts, and calendaring.
With Office 365, you still use Outlook (installed on your local computer) but instead of connecting to an Exchange server managed by your IT team, you connect to an Exchange server managed by Microsoft.