This knowledgebase aims to explain everything there is to know about Focus and the Timespace Platform. It is very much a work in progress and its driving force are questions asked by users. So if you can't find what you are looking for, ask by sending mail to firstname.lastname@example.org. We'll help you and then add documentation for others to see, too.
Each activity and indeed all content belongs to a cloud. The permission lists in a cloud define who can see and access the content.
Focus gets its name from its most prominent feature, focus. When focused, the app tracks your time and shares your focus with others in the cloud of the activity. Focusing also sets the context to which content is added from e.g. email or Dropbox. The FAQ explains this in more detail.
When you are focused, you'll feel better all the while getting more work done. Companies can buy support, sponsor premium Focus accounts to employees and even run business processes and workflows on top of Focus.