We use it to collaborate. We use it for documentation management, to collaborate with Microsoft Teams, web calls, web conference calls, chats, and as a documentation repository mainly. We have an Office pack suite to be able to write documentation, make spreadsheets, and create PowerPoints.
We are also using Microsoft Bookings to have calendars and automatic booking with people. At the moment, we are also using Microsoft Flow to be able to integrate between our CRM and SharePoint.