Anti-tank vehicles made their first major appearance in World War II. Typically, these vehicles mounted a high-velocity cannon on a relatively light tracked chassis. As a consequence, they sacrificed armor for speed and manuverability. They met with only limited success.
Modern vehicles typically employ a guided missle, often wire-guided. Some modern force structures do not employ dedicated anti-tank vehicles. For example, the U.S. Army has vehicles (such as the M113? armored personnel carrier), which may mount anti-tank missles for defense, but that is not their primary role.