Office Online vs. regular Microsoft Office
While the Microsoft Office desktop version generally has many many more advanced features available than its online cousin, Office Online is rich in ready-made templates and collaboration features which allows multiple people to edit a document or spreadsheet simultaneously. With the advent of Office Online, users who do not have the desktop version of Microsoft Office can easily work together with those who do. As the name implies, though, Office Online does require a constant connection to the internet. Though documents created online can be downloaded to a computer, they can't be edited offline unless you have a compatible version of the desktop software.