Category is dedicated for nodes and any activities related to them including troubleshooting, offical tutorials or steps, support question and various node related discussion. Feel free to create a new topic, but do not forget to choose a relevant topic tag so that all community users would be able to distinguish the topic content correctly.
By default if you need a help with your own nodes flag the topic as support-request.
For frequently questioned topics there would be posted tutorials how to handle specific cases, such topics would be marked with troubleshooting, faq or official.