Microsoft Office 365 for professionals and small businesses is a subscription service that combines the familiar Microsoft Office Web Apps with a set of web-enabled tools that are easy to learn and use, that work with your existing hardware, and that come backed by the robust security, reliability, and control you need to run your business.
Email & calendar
Office Web Apps
Websites & collaboration
99.9% uptime guarantee
Find and connect with friends or peers from virtually anywhere through rich presence, instant messaging (IM), PC-to-PC audio/video calls, and online meetings. Use the presence indicator to see when colleagues, partners, and suppliers are online and available.
Conduct rich online meetings—including audio, video, and web conferencing—with people both inside and outside of your business.
Note: All the information is taken from the official Microsoft website