Microsoft Teams replaced Skype for Business as Microsoft's audio and video conferencing tool. But it's so much more than that, It's also:
Microsoft Teams is the cornerstone of Microsoft’s modern workplace. It can be accessed online through the browser or an installed desktop application. Teams is built on Office 365 Groups, which provides a team of people a space for collaboration. It connects many other Office 365 applications such as Planner, OneNote and SharePoint, and has replaced other tools such as StaffHub and Skype for Business. At its core, Teams is a series of tabs that connect to other systems and pages, as well as an out-of-the-box instant messaging platform, with voice and video calls, screen sharing, external sharing, and collaboration. It’s easy-to-use and clean user experience is intuitive and easy to adopt.