What kinds of documents do professional software developers write?

For a project in one of my university courses I need to write a paper with details of some kind of document that people in our field would write when actually working. I'm only in my second year right now so I'm not sure what documents and things like that I would be responsible for. I have thought about project proposals, code documentation, and bug reports. Is there anything else important that could be a little more well defined and longer in length?