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Direct message channels are used to start direct messaging with one or more users. Channel members are determined when creating a channel and cannot be changed later. Also direct message channels are more limited compared to other channel types.
Case Management
Channels may also have a case list to be tracked by members by enabling case management on channel properties.have a case management feature to manage tracked topics in addition to messaging. Case management feature is disabled by default but can be enabled by selecting edit from channel menu.
When enabled channel view split to sections to show channel activities and case list. Please see Cases page for more details.
Cases can be created by manual user entry or automatically by email or integration with web hooks. Each case has an automatically incremented number to easy referencing. Case number starts from 1 for each channel.