camunda is a software for business process automation: You create a diagram that shows exactly what should happen in your process, and then you let camunda execute it. Camunda will assign tasks to the users you specified, and/or it will invoke API services in other applications. When the task is done or the service completed, camunda will proceed to the next steps following the path you specified, including forks, joints and even events. Meanwhile you can monitor the process execution in real-time: The diagram you created will be displayed and annotated with all the runtime information you need.
Why should you want that? When scaling up your business, you need to structure and automate everything that is repeatable. By doing so, you ensure the daily work will be done in a consistent way, even when rapidly growing your staff. You're also saving money, because a lot of the work that would have to be done manually can now happen automatically which also speeds up your processes.