I am creating a form with the file upload feature. There is the option to choose the file type as either 'document' or 'image'. I would like to know exactly what file types are considered 'document' and which are 'image'. More importantly, it is possible to choose both? If not, this could be quite limiting. For example, I would like to give my users the opportunity to add either pdfs or jpgs but through the use of just one button/field.