Slack is a cloud-based team communication and collaboration platform developed by Slack Technologies, which has been owned by Salesforce since 2021. It is designed primarily as a business-to-business service, catering to team-based businesses with functionalities focused on business administration and communication. Slack offers features similar to Internet Relay Chat (IRC), including channels organized by topic, private groups, and direct messaging. Users can search for files, conversations, and people within Slack, and express reactions with emojis. Slack also integrates with third-party services like Google Drive, Trello, and Dropbox.
Key features include direct messaging, channels for organizing communications, Slack Connect for external collaboration, and Huddles for audio and video calls. Slack also provides tools for automating routine tasks, sharing knowledge, and managing focus by reducing context-switching. Slack offers a "status" feature, allowing users to share their availability and activities with teammates. As of January 2026, a new Slackbot AI assistant is available, offering intelligent search and retrieval, document analysis, calendar management, and content creation capabilities.
Slack operates on a freemium model with various paid plans that offer benefits such as unlimited message history, more app integrations, and group video calls with more participants. As of 2026, the pricing plans include a free version with limited features, Pro at $7.25 per user per month (annually), Business+ at $12.50 per user per month (annually), and Enterprise Grid with custom pricing. The Business+ plan includes AI features and SSO. Slack is available worldwide and supports multiple languages, making it suitable for international teams.