The game has the player remotely control a futuristic robot tank, whose mission is to stop enemy rebel tanks rampaging across the countryside from reaching downtown Santa Clara. The tank is equipped with radar to locate enemy squadrons.
The game was innovative in that, instead of the player's tank being destroyed with a hit from an enemy, it was merely damaged, losing some capabilities such as radar or speed (enough damage would eventually destroy the tank). The game also features 24-hour gameplay (that is, combat could take place at any time of the day or night) and varying weather (rain, snow, fog), which added additional challenge in tracking enemy combatants.
Source: Wikipedia, "Robot Tank," available under the CC-BY-SA License.