You will find that the Excel Web App is still Microsoft Office Excel but it does have some differences. For one thing, Excel runs on your computer, and Excel Web App runs out in the cloud and you access it by using your web browser.

Microsoft Office Excel is one of the most popular data analysis tools on the planet. Using Excel, you can enter numbers into a spreadsheet and use functions to manipulate them and perform analysis. In addition to analyzing numbers, Excel is often used for tracking and managing other data, such as customers, for example. In many organizations Excel has turned into a database-type application where all types of information is stored.

Excel is what is known as a thick client in that it runs from your local computer. You click Start→All Programs and you browse to your office applications and you click Excel to fire up the program. Excel then runs on your computer.

A web-based application, on the other hand, runs on a computer in a data center that you access over the Internet. If you use Hotmail for e-mail or browse a web page, then you are using a web application. The way you access a web application is by using a web browser, which is a program installed on your computer.

When you create a document on your local computer with Excel, that document is stored locally on your computer. When you click the Save button to save a document, you are prompted for the directory on your local computer in which to save the file. You may save the file to your Desktop or any other folder on your computer.

In any case, your creation is a physical file located on your local computer. When working with the Excel Web App, however, you do not have a local physical file. When you create a document and save it, your document lives on a computer in one of Microsoft’s data centers.

Because you don’t know exactly which computer in which Microsoft data center, you can just say that the document lives out in the cloud. In the case of Office 365, your document lives within a SharePoint Online document library.

You don’t have to be a subscriber to Office 365 to work with Excel Web App. You can use it for personal use for free with a Windows Live account.