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. Users can communicate through text messaging, file and media sharing, voice and video calls in private chats or within communities called "workspaces." The application incorporates IRC-style elements such as persistent chat rooms organized by topic, private groups, and direct messaging. In addition to these online communication features, Slack can integrate with other software. Slack can be accessed through web browsers, and dedicated clients are available for Windows, Linux, MacOS, Android, and iOS. In the past, a client was also available for Windows Phone devices, but support for it was discontinued in June 2018.