The User groups feature can reflect a logical or some different kind of physical organization of your company. If this is large, you may want to spend some time thinking about how to organize groups. Your company may have multiple office locations, so as an example scenario, you may have a London office and be able to assign issues to the group called London office. Afterwards, everyone in the London office will get the notification e-mail and a worker named John Doe can take the task and immediately start to work on it.
Before creating User groups, make sure the following is done: