I often hear the two words in the same sentence, but never actually took the time to find out what the two mean.
From the general usage you could say that tactics is something short term and based on particular cases and actions with them.
On the other hand a strategy faces types of problems and the general guidelines how to deal with them.
I found a very nice definition of the two at: http://www.molossia.org/milacademy/strategy.html
Military strategy and tactics are essential to the conduct of warfare. Broadly stated, strategy is the planning, coordination, and general direction of military operations to meet overall political and military objectives. Tactics implement strategy by short-term decisions on the movement of troops and employment of weapons on the field of battle.
The great military theorist Carl von Clausewitz put it another way: “Tactics is the art of using troops in battle; strategy is the art of using battles to win the war.” Strategy and tactics, however, have been viewed differently in almost every era of history. The change in the meaning of these terms over time has been basically one of scope as the nature of war and society has changed and as technology has changed. Strategy, for example, literally means “the art of the general” (from the Greek strategos) and originally signified the purely military planning of a campaign. Thus until the 17th and 18th centuries strategy included to varying degrees such problems as fortification, maneuver, and supply. In the 19th and 20th centuries, however, with the rise of mass ideologies, vast conscript armies, global alliances, and rapid technological change, military strategy became difficult to distinguish from national policy or “grand strategy,” that is, the proper planning and utilization of the entire resources of a society–military, technological, economic, and political. The change in the scope and meaning of tactics over time has been largely due to enormous changes in technology. Tactics have always been difficult–and have become increasingly difficult–to distinguish in reality from strategy because the two are so interdependent. (Indeed, in the 20th century, tactics have been termed operational strategy.) Strategy is limited by what tactics are possible; given the size, training, and morale of forces, type and number of weapons available, terrain, weather, and quality and location of enemy forces, the tactics to be used are dependent on strategic considerations.
An application of this to a business environment can be seen at: http://www.thinkingmanagers.com/management/strategy-tactics.php