Microsoft is introducing a free version of Teams today, the company's Slack competitor. ... The free version includes built-in audio and video calling for groups, and even unlimited app integrations for adding apps like Trello to Microsoft Teams. Microsoft Teams was born as a competitor to Slack. The online coming together of app integrates Microsoft Office 365 with group chat software and a host of productivity tools. On its face, Microsoft Teams looks exceedingly similar in look and feel to Slack.The idea behind the Wiki is that it's a place where team members can share notes in a somewhat more structured way than exists in channel conversations.