Microsoft's cloud service was down with an unexpected global outage across multiple regions. The company's support page indicates that there's an issue across the storage layer in many regions.
The outage affected many of Microsoft's products and services, such as OneDrive, most of the company's official blogs, Windows Store, Tweetium app wouldn't function properly, Xbox Live left with issues, the official DVLUP Windows Phone developer website was offline, Microsoft Band wouldn't sync, and so forth.
Others that were hosted on Azure such as Storage, Websites, Azure Search, Azure Cache, Management Portal, Service Bus, Event Hubs, Visual Studio, Machine Learning, HDInsights, Automation, Virtual Network, Stream Analytics, and Active Directory, are all affected.