The Community College of Baltimore County: Gary E. Kaiser's "Sizes, Shapes, and Arrangements of Bacteria"
Read this page. Click on every embedded hyperlink, and explore the linked contents. Finally, click on "Quiz Yourself on This Section" to test your knowledge.
Click http://web.archive.org/web/20160624212606/http://faculty.ccbcmd.edu/courses/bio141/lecguide/unit1/shape/shape.html link to open resource.