Don’t get us wrong—email is great. But sometimes there’s too much of it at work, as colleagues share information too broadly or chime in unnecessarily, and as marketing offers and other junk fills your inbox. Over the past few years, lots of organizations—including small and large firms, non-profits, academic departments, student project teams, and government agencies—have moved their internal communications to the group messaging service Slack, which is free but includes paid plans with additional features. It’s also possible to make public groups that anyone can join.

Slack, which has apps for macOS, iOS (iPhone and iPad), Windows, and Android, isn’t conceptually all that different from Apple’s Messages app. You type short messages and other people in the conversation can reply. You can share graphics or other files in the discussion, and search through past messages. Slack supports person-to-person voice calls, and if you switch from a free to a paid team, group calls, video conferencing, and screen sharing.

What sets Slack apart from simple messaging apps is that it lets you segment discussions into “channels,” which can either be public, such that everyone in the team can see them, or private, so only invitees can participate. Plus, you can have “direct message” conversations with individuals or small groups.

The beauty of Slack channels is that they’re easy to create and they bring together all communications relevant to a particular workgroup, project, or topic. You might have a private #marketing channel for everyone in that department, a private #annual-report channel for the people who need to put together that document, and a public #facilities channel to talk about burnt-out lightbulbs and stuck doors. That’s way better than organization-wide mailing lists, since you can pay attention to just those channels that matter to you, and ignore the others.

How do you keep up on discussions? Slack has flexible notifications, letting you choose at the top level to be notified about everything; just direct messages, mentions, and keywords; or nothing. You can also choose to be notified of replies to threads you’re in. Then you can override those defaults for any channel or conversation you’re in, which lets you make sure that important messages get through and water cooler chatter doesn’t interrupt you. Plus, if you leave your computer, Slack can repoint notifications to your mobile devices automatically, with separate settings to make sure you aren’t overly nagged while at your kid’s soccer game.

Slack provides tons of other features that can prove useful in organizations of any size. You can share and comment on files of any type, which is far more effective than sending attachments around in email. You can create “posts” and get others to edit them collaboratively—a boon when trying to craft the perfect bit of text for some purpose. And you can integrate hundreds of Internet services into Slack so it can act as a single dashboard for many other apps.

There’s no question that setting up Slack for your team is a major step, but the fact that it has become so popular—77% of Fortune 100 companies use it—shows that it can make your organization’s internal communications faster, more targeted, and more effective. It’s not hard to set up and maintain, but give us a call to talk about the best ways to begin.