We all know the song, When Cap throws his Shield, the Bad Guys are in for a world of hurt. This article will focus on Caps trusty ol' Shield.
In the beginning, Caps' shield was the coat-of-arms type that was more for defense than offense. It was far from bullet proof but in hand to hand combat, a shield bash could knock an opponent out.
shortly before Caps' last WWII mission, Howard Stark produced for him the now classic vibranium disc shaped shield based on a Greek Hoplite's shield or "Hoplon".
The energy absorbing properties of the vibranium shield allowed it to ricochet off objects much like a pinball. Cap quickly learned to work angles like a champion billiards player to take down multiple bad-guys and still have it end up in his hands.
Later, when the Government stripped Steve Rogers of his shield (and gave it to US Agent) Steve Rogers went by "The Captain" and Tony Stark made him an Adamantium shield. In the Secret Invasion, The Skrulls shattered Caps' Vibranium shield and Stark made him a holographic shield that worked like a force field.
It will be interesting to see in [The Avengers: Age Of Ultron](movie:293035) how Caps' vibranium shield will hold up against Ultron if he himself is made of either Adamantium or Vibranium.