Microsoft has introduced a new version of their trusted Office productivity suite and home consumers essentially have to make a choice between Microsoft Office 2013 and Office 365.
Microsoft Office 2013, like the previous versions, is a bundle of core Office programs including Word, Excel, PowerPoint and OneNote. A single license would allow you to install the Office suite on just one Windows PC.
Microsoft Office 365 is a suite of the same Office programs but here you have an option to install Office on up to five different Windows PCs or Macs. There are not product keys to enter as everything is tied to your Microsoft account. You also get 20 GB of extra storage space on SkyDrive with Office 365.