Each human task has to be assigned to a human to fulfill it. Such a human is called a participant. Generally, we can assign a human task to a specific user or group of users. In the latter case, a user has to claim a task before he can start working on it. We assign a human task to a specific user if we know exactly who should fulfill the task. Otherwise, we can assign the task to a group, and a user (for example an employee) from that group can claim the task and fulfill it.
To simplify our example, we will assign the human task to a specific user: