Slack – a corporate messenger with the flexible working chats to improve the productivity and interaction between employees. The software allows you to create the thematic chats which can be structured in different directions or projects. The main functions of the Slack chat include are the browsing of the messaging archive, search for the sent files by keywords or date, configuration of the notifications, pinning of the posts, etc. Slack enables to make video calls, watch videos without going to the source website and add comments to the messages. Also Slack supports the integration with a large number of the external services that allows to browse email, communicate on the different social networks and share files using the cloud storage inside the messenger.