Note: Office 2016 is now available.  However, this overview still gives you a good understanding of the Microsoft Office options available to you.  Source: Word 2013: Buying Office 2013

In January 2013, Microsoft released the latest version of its Office software suite, Office 2013. It also released Office 365 Home, a subscription-based version of Office. If you’re thinking of purchasing or upgrading to Office 2013, there are several factors to consider, including the cost and features of each version.All about Office 2013The Microsoft Office suite is an essential collection of applications that includes Word, Excel, PowerPoint, and much more. Office 2013, the latest version of the Office suite, includes some significant changes. Microsoft is now offering Office through a yearly subscription plan, and the company has heavily integrated it with its Microsoft account and OneDrive (previously known as SkyDrive). Therefore, it’s important to understand the different services and available purchasing options before you buy.

Source: Word 2013: Buying Office 2013