Reading in Scalar
Finding your way in Scalar
At the top-left of the Scalar header, you'll find a series of icons. Rolling over the compass icon
reveals a number of options for readers to orient themselves in the current book, including recently viewed items and a set of global visualizations.Recent Items. Recently viewed pages in the current Scalar book items are stored in the "Recent" menu in reverse chronological order.
Global Visualizations. Unlike visualizations for individual pages, visualizations accessed via the Scalar header display content and connections for an entire book, based on critera set by the reader. Readers can choose the "Format" for the visualization, that is, how the connections between content is visualized (choices include: Grid, Tree, Radial and Force-directed); the type of content to be visualized (choices include: All content, Table of contents, All pages, All paths, All tags, All annotations, All media, All comments, or Current page); and the type of connections or relationships to be visualized (choices include: All relationships, Parents and children or No relationships).
Index. Rolling over the menu icon
in the Scalar header will reveal the Index 
icon, located just below the main table of contents. The index contains a hyperlinked catalog of all content in the current book. The content is divided up, for the reader's convenience, into tabbed categories (Paths, Pages, Media, Tags, Annotations and Comments).
Text
While text itself needs no introduction, its appearance in Scalar bears mentioning a few items of note:
Media Links. Each media link is preceded by an icon for the type of media it references; clicking a link to a time-based media file causes it to start (and subsequently to stop) playing.
Notes links. These links are preceded by a note icon and serve a similar function as footnotes, displaying additional content when clicked.
Media
Embedded media files have a few extra features that go beyond simple playback and viewing. The Details button in the lower left corner of the media opens an expanded view in which all aspects of the media file, from annotations to metadata, can be examined. Clicking "Permalink" will take you to the media's dedicated page, and clicking "Popout" will open the media file itself in a new window.
If a media file has annotations, they will be available in different ways depending on the media type and display method. In some cases, an "Annotations" link will toggle the display of all of the file's annotations, which can be individually clicked; in others, you'll need to click the "Details" link to access them. For text and time-based media, pop-up "live annotations" will be displayed when the media is cued up to an annotated region.
Paths
Paths are sequences of pages--like chapters in a book, but more flexible. You'll know you're about to embark on a path when you see a "Begin this path" button at the bottom of a page, with a table of contents beneath. Clicking the button (or on any of the listed pages) will take you into the path. Once you're on a path, additional navigation at the top and bottom of the page identifies the name of the path you're on, how far you've traveled, and provides links to move stepwise along the path. Sometimes paths lead to other paths; other times they lead back to the "Home" page of the book.
If you want to get a better sense of the structure of all of the paths in a book, try the Path Visualization.
Tags
Tags are markers that are applied to pages that have something in common. If the page you're looking at has been tagged, you'll see a "Tagged by" at the bottom of the page, followed by the name of the tag (or tags) which act as links to other pieces of content that share the same tag (or tags).
If you want to see how tags in a book are interrelated, try the Tag Visualization.
Comments
Any reader is free to submit a comment on any page or media file in a Scalar book by clicking the "Comment on" link at the bottom of the content, whether or not they have a Scalar account. It's even possible to add a comment to another comment in threaded fashion. New comments, however, will not be visible within the book until approved to go live by an author user for the book.