Page History

The sidebar on the page (first image) lists the information sources Bob has
registered,
and also the filter tags he has made.  Bob selects the particular
sources
from which he is interested in consuming information right now,
and they are displayed in the center as a scrollable list. Contrast this
with Design 1, in which all sources were interleaved and the sidebar was
not present. There are controls for tagging and saving each item which
he uses to do the second and third tasks (not depicted in this image,
but would be similar to Design 1's controls).