@startuml
mainframe Appointment
start
:Asking Appointment]
repeat
if (accepted) is (yes) then
	:Export to calendar]
	stop
else (no)
	:Propose new appointment]
endif
	
@enduml

@startuml
mainframe Messaging
start
split 
	:Create Discution]
	:Choose users]
split again
	:Message one users]
endsplit
repeat :send Message]
repeat while
stop
@enduml

@startuml
mainframe Forum
start
:Forum Creation]

repeat
:Topic Creation]
:Topic Answering]

repeat while
stop
@enduml