Slack (APIs.json)
Slack is a cloud-based freemium cross-platform instant messaging service created by Slack Technologies and currently owned by Salesforce. While initially developed for professional and organizational communications, it has also been adopted as a community platform.
Slack Web API
The Slack Web API is an interface for querying information from and enacting change in a Slack workspace. Use it for individual queries, or as part of a more complex tapestry of platform features in a Slack app.