Office 365. Office Web Apps. Office 2013. Buying Microsoft Office has never been more confusing, thanks to Microsoft adding a new subscription program for home users in addition to the already available web-based Office and traditional desktop suite. Which one is right for you? Let's take a look.
Office 2013: First, there's Office 2013, which is the easiest to understand. It's the desktop software update to Office 2010. Office 2013 RT (a version just for Windows RT tablet users) is expected to start shipping this month, with fuller-edition, boxed versions for Windows 7 and Windows 8 users available later.
Office 2013 offers a number of enhancements over Office 2010, including touch-optimized controls, better graphics support, and integration with SkyDrive. One of the coolest features is you can start working on a document on one device and then continue where you left off on another, because Office saves your exact location in the doc. The single user, single PC version of Office 2013 Home & Student is priced at $119.99. If you bought Office 2010 after October 19 or buy it before April 30, 2013, you can get a free upgrade to Office 2013.
Office 365: New for home users is Office 365, which is a subscription service to Office. Instead of paying for a boxed or downloaded copy of Office, you can "rent" it for $99.99 a year. Why on earth would you pay every year to use the software you can buy just once? For one thing, Office 365 Home Premium includes not just the four "core" programs offered in Office 2013 (Word, Excel, PowerPoint, and OneNote), it adds Publisher and Access. The equivalent Office 2013 suite with Publisher and Access--Office Professional--will cost $399.99. The Office 365 subscription also gives you 20GB of extra SkyDrive storage and 60 minutes of Skype calls, plus the license is good for five users across a mix of five PCs or Macs.
In other words, it might be a better value if you have more than a few devices you want to run Office on and need Access and/or Publisher.
Office Web Apps: And then there's Office Web Apps, Microsoft's free version of Office in the cloud that has been available since 2010. These web-based versions of Word, Excel, PowerPoint, and OneNote (plus Microsoft's new Outlook.com email service) are available through SkyDrive at http://skydrive.live.com. Office Web Apps have become increasingly capable, with features like commenting in Word, charting in Excel, transitions in PowerPoint, and ink recognition in OneNote.
Depending on your usage, Office Web Apps may be all you need. Since I can't find anywhere a comprehensive list comparing what's in Office 2013 or 365 versus Office Web Apps, the only way you can really tell if Office Web Apps has all the features you need is to try the service out.
If not, Office 365 is available as a preview, and you can also download a 60-day trial of Microsoft Office 2013 Professional Plus from Technet.