Microsoft Azure is an open, flexible, enterprise-grade cloud computing platform. Azure is a collection of intergrated cloud services, Including but not limited to Analytics, Computing, Databases, Mobile, Networking, Storage and Web
MS Office 365
Is a Subscription plan application that has all your office applications, word, excel, outlook, as well as offers features including and not limited to include services such as Skype for Business web conferencing and Exchange Online hosted email for business, and additional online storage with OneDrive for Business.
Skype for Business
An application that allows you to collaborate with anyone, anywhere, on any device. All this under the security and control of Microsoft.