Office 365 Business is a cloud-based subscription service that provides modern Office applications on up to 5 PCs or Macs, as well as Office apps for smartphones, tablets, and iPads. It offers the full installed Office desktop apps, access to Office Online for editing files from any browser, and 1TB of cloud storage. The service aims to improve productivity through collaboration tools that allow real-time co-authoring and sharing of files with others inside and outside an organization. It also provides built-in security and auto-updating of apps to keep devices protected and up-to-date.