Microsoft Office 365 is a Web-based version of Microsoft's Office suite of enterprise-grade productivity applications.
Office 365 is delivered to users through the cloud and includes Exchange Online for email, SharePoint Online for collaboration.
If you are interested, Microsoft Office 365 Home Premium is being sold in the subscription model, and it costs $99 per year for an entire household to install. This price can vary, according to the purchase source.
Office 365 is basically a subscription plan given by Microsoft office which includes access to office applications. It includes the plan that users can use for home and for business. Business service includes an exchange server, skype for conferencing, SharePoint etc. To use it at home it got some exclusive features with it like ink math assistant, quick starter any many more. Like Microsoft says it is the office you know and can trust. the prices are different for home-based and businesses based service. If interested go for it.