Powerful tool for team collaboration

Easy to use interface, very simple. Most of the settings can be customized to fit the user's preferences. I can use Slack on both my phone and my laptop and it syncs close to real time. There is the issue of the overwhelming amount of notifications, and the less than great file search, but overall the tool is very easy to use.

Slack is great for project-based work. You can organize channels and conversations around specific projects. You can use #s to keep discussions organized, and provide updates while certain users are still offline.

Slack is not the best suited for knowledge base management or heavy document management. It is often difficult to search for files that were once shared, and there are also size limits on files.