In ProcessMaker, a "Request" is a single occurrence of a Process. A Request is more than just starting a Process. A Request is the workflow routing of one incident of a Process.
This is called a “Request” because many Processes begin with a request for an approval or a decision. Below are a few examples:
Request approval for a budget.
Request a leave of absence for next week.
Request to purchase office supplies.
You may start a Request for Processes that you have permission to do so. Likewise, you can participate in others' Requests. This occurs when someone else in your organization starts a Request that involves you. You would be notified of the Request and that you have a Task to do. You might be the only person deciding on a Request, or you might be among other users involved in the workflow routing of a Request for a Process.