Ever since its introduction, Microsoft's Teams—a collaboration tool for chatting, sharing documents, video, and voice calling—has had one major competitor: Slack. Teams was clearly built as a response to Slack's growing enterprise presence, with its model of IRC-style chatrooms winning hearts and minds.

Thus far, Microsoft has pushed Teams' extensive integration with the company's other products—Office, Skype, SharePoint—as its major distinguishing feature, but Slack has had one important capability that Teams has lacked. The starting price for Slack is free. The free version has all sorts of limitations—only 5GB of files can be saved, only 10,000 lines of chat can be viewed, and integrations with other applications are restricted—but it's enough to get a sense of how the product works and how it can fit in an organization. The free version also means that Slack has found a role in various non-paying spheres, such as open source development, serving a similar role to the one once served by IRC.

Today, Microsoft is offering a free version of Teams that anyone can sign up to and use. Like the free Slack tier, there are limitations to the free Teams, but Microsoft has picked a very different set of restrictions than Slack's. There's no 10,000 message limit—even free users can access and search all their chat history—and the data limits are substantially higher, at 10GB plus 2GB per person. Free Teams supports group voice and video calling, too; Slack's free tier is restricted to 1:1 video calls. Application integrations are unrestricted, and Microsoft is of course continuing to promote the tie-ins with the online versions of Word, Excel, PowerPoint, and OneNote.

On the other hand, the free Teams is limited to 300 people. Slack, in contrast, has no such limit.

Microsoft is also promoting some new features for all Teams users, both paid and unpaid. Coming later this year is a background blur feature for video chatting. If this works as well as it appeared to work in a brief demo, it will be a welcome addition for those of us that work from home, as it should do a fine job of masking the messy living rooms and misbehaving cats that so often conspire to make home workers look a little less than professional.

Microsoft is also integrating its translation technology to improve collaboration between multi-language teams (available now for paid users, later in the year for free ones). For paying users only, the company has also added automatic recording and transcription of video calls.