SharePoint is a cloud-based service that provides tools for communication, collaboration, and productivity for businesses and users. It includes services such as SharePoint Online, OneDrive, Yammer, Exchange Online, and Lync Online. SharePoint uses a service-oriented architecture and supports three types of apps: provider hosted apps, SharePoint hosted apps, and auto-hosted apps in the cloud. Licensing for SharePoint depends on usage scenarios such as intranet, extranet, or internet. SharePoint centralizes administration and allows customization, collaboration, security, and ease of use.