The inline grading feature that you'll be using in Canvas is called SpeedGrader. SpeedGrader makes it possible to view and grade student assignment submissions in one place. In SpeedGrader you can use a simple point scale, or a complex rubric, and you can use the Crocodoc markup feature to annotate comments directly on student paper submissions. At present Crocodoc is only compatible with .doc/.docx, .ppt/.pptx, and .pdf file types. You can also leave text, file attachment, and media comments for students through the SpeedGrader interface.