Office Web Apps Front and Back
By default, when you open a Word, Excel, PowerPoint, or OneNote document from a SharePoint document library, the file is opened directly in the browser by using Office Web Apps. Although you’re viewing the document through a browser, you will experience the same look and feel as if you were to open them in a desktop application.
Office Web Apps is designed for light editing with many commonly used editing features, such as clipboard, fonts, paragraph, styles, and spelling. You can insert tables, pictures, clip art, and links directly from the web app, as well as toggle between the Editing view and the Reading view.
If you need to use the full set of features of your Office desktop application, open your document with your desktop application by clicking the Open in [Office App] icon on the Ribbon.
Supported file types and oddities in Office Web Apps
New files created in Office 365 are based on Office Open XML file formats — think of the four-character extensions, such as docx, .xlxs, .pptx, and so on. Not to worry, SharePoint online is configured with Word, Excel, and PowerPoint templates that are compatible with Office Web Apps. The OneNote web app on the other hand, will open a blank OneNote 2010 notebook when you create a new file.
Unlike the other web app files, a new OneNote notebook file is actually a folder with another file named Untitled Section.one inside of it. This is the default name until you change the name of the section.
Supported file types for Office Web Apps are as follows:
Viewing and editing: .docx, .xlxs, .xlsb, .pptx, .ppsx, .one
Viewing only: .doc, .dotm, .dotx, .ppt, .pps, . pptm, .potm, .ppam, .potx, .ppsm
Macro files for Word (.docm) can be edited in Office Web Apps, but the macros will not be run. For macro Excel files (.xlsm), Office Web App will strip the macros and prompt the user to save a copy of the file with macros removed.
Coauthoring in Office Web Apps versus Office 2010 is not the same. In Office Web App, you can have multiple users editing a document simultaneously only in Excel and OneNote (not Word or PowerPoint). In Office 2010, coauthoring works in Word, PowerPoint, and OneNote only (not Excel).
The engine behind the Office Web Apps user experience
When you open a document in Office Web App, a whole series of processes and services occur behind the scenes, all within the few seconds between the time you click on the file and when the browser renders the file for you to view.
HTML (Hyper Text Markup Language) is the wrapper that gives your candy or package the right look and feel. In the world of websites and web pages, HTML is what makes text appear in bold or a picture align left or right. For example, if you want to have the phrase Office 365 appear bold on a web page, you would use the following HTML tags.
Silverlight enhances your web experience by loading pages faster, improved text fidelity, smoother animations in PowerPoint, presentation slides that grow or shrink depending on the size of the browser, and much more. Silverlight is not required to run Office Web Apps, but it would be a mistake not to take advantage of this free web browser plug-in.
So the next time you use Office Web App, think of all the processes, services, events, and instances happening in the background to provide you with the best viewing pleasure. Actually, you probably won’t think about it because the geniuses behind Office Web Apps designed it to go so fast you’re not supposed to notice it.