Tension-is an internal axial member fforcce that tends to lengthen a member

Compression- is an internal axial member force that tends to shorten a member

Through Truss-is a truss whose deck is located at or very near the bottom chord; thus vehicles pass between the two main trusses as they cross the bridge

Pony Truss- looks just like a through truss, except it is not as high and has no lateral bracing between the top chords.

Deck truss- is a truss whose deck is located at or very near thee top chord; thus vehicles cross the bridge on top of the trusses.

Force- a push or pull

Load-are forces applied to a structure

Deck-is the floor of a bridge.

Yield stress- is the strength of a metal. It is the force per unit area at which the metal fails by yielding.

Span- is its length from support to support

Buckling-is the principal failure mode of a member that is loaded in compression.