Slack

Slack is a channel-based messaging platform that organizes team communication around topics, projects, and teams rather than scattered inboxes. Conversations live in channels — public, private, or shared with outside organizations via Slack Connect — so context is searchable and newcomers can catch up. Threads keep discussions tidy, huddles offer lightweight audio/video, and clips let people share quick recordings, making Slack a hub for both real-time and asynchronous work. Beyond chat, Slack is a work platform. Workflow Builder automates routine processes without code, canvases capture shared docs and knowledge alongside conversations, and lists track lightweight work. Its deep integration ecosystem connects thousands of apps — Google Workspace, Salesforce, Jira, GitHub, and more — so notifications and actions happen where teams already talk. Slack AI adds channel recaps, thread summaries, and AI search across the workspace, turning conversation history into answers. Owned by Salesforce, Slack serves teams from startups to global enterprises, with enterprise-grade security, compliance, data controls, and the Enterprise Grid architecture for large, multi-workspace organizations. Pricing is per active user: a free plan with limited history, then Pro and Business+ tiers, with Enterprise Grid quoted for scale. It competes with Microsoft Teams, Google Chat, and Discord, differentiating on its integration ecosystem, search, and developer platform.