Presence is another example of something which is being powered by attention in Composer. Once you're in deck having something open is a little less meaningful of a signal. Attention allows the noise in that signal to be reduced by indicating more clearly what someone is currently working on.

The complementary sidebar in Composer is one example of attention in action. With it, we're easily able to control the context of the sidebar based on the currently attended item.

In the deck, clicking on something in the sidebar will open a new plank or scroll to the plank if it's already open. Alt-clicking will close thing or they can be closed from the plank itself.

Currently there is only one deck in Composer and it is effectively a mode. First time users enter in "solo mode" where one plank fills up the whole main area. Exiting solo mode adds that current plank into the deck and displays the deck.

A core part of the default layout in Composer is a component we call the "deck". If you've ever used TweetDeck or @deck.blue the basic layout should make sense, except in this case we've repurposed it to serve as a multi-tasking surface for knowledge work.

One view into data that we've been experimenting with in Composer is what we call a "stack". A stack is a transclusive view of an ordered collection of objects laid out vertically.