Navigation Icons

Naviagtion icons take the form of a button bar at the top of each page, and (usually) a single button at the bottom. The button bar looks like:

[previous_group] [previous] [up] [next] [next_page]

The icons and their meanings are:

[previous_group] Move to the beginning of the previous lecture.
[previous] Move to the previous page in this lecture.
[up] Move up one level, returning to the Course home page.
[next] Move to the next page in this lecture.
[next_group] Move to the beginning of the next lecture.
Toggle color/nocolor versions of this page (if it exists).
An unhighlighted button with a border indicates the page is not yet available, for example:

[next_group]

A button with no border indicates the page does not exist, for example

or