Taken at Forester's Hall in Redwood City, this type of truss uses metal rods along the bottom to resist tension forces.  This type of truss is shown at the right of the diagram.
  The steel rods in the previous picture bend up and into the ceiling space.
  This interactive model will let you see which forces occur where within a truss you construct.
  From the Brantacan Bridges site, examples of truss bridges.
The idea of forces held apart by a distance leads us to trusses.  The straw and paper clip shapes you made earlier this year were relatives of the truss.

The diagrams above are examples of simple trusses.  At this point, I'd like you to note that the loads applied to the top of the truss are distributed equally to the ends of the trusses or bearing points.  Another way of saying this is that the loads are distributed equally to the reaction points.

Trusses work by accepting loads at their connection points and distributing them through the diagonal web members and the top and bottom horizontal members called chords.  In our previous examples, the compression forces were mostly in the top flange of the beam.  Here, those forces are confined to the top chord member.  Tension forces are confined to the bottom chord member.

Let's kick it up a notch!