In strategy computer games, of both the turn-based and real-time varieties, a tech tree, short for "technology tree," is an abstract hierarchical visual representation of the possible paths of research a player can take.

Typically, at the beginning of a session of a strategy game, a player may only have a few options for technologies to research. Each technology that a player researches will open up more options, but may or may not, depending on the computer game the player is playing, close off the paths to other options. The tech tree is the representation of all possible paths of research a player can take. A tech tree appears visually similar to a tree, with many branches, because technological research in these games tend not to be linear.

A player who is engaged in research activities is said to be "teching up," "going up the tech tree," or "moving up the tech tree." Experienced players of a game will likely be aware of all possible branches of the tech tree for that game, as knowing what options specific choices of research open up allows the player to make fast and informed decisions on what to build or research, translating into a significant advantage over players with less knowledge of the tech tree for that game. Analysis of a tech tree can lead players to memorize and use specific build orders.

Tech trees are implemented in various ways. Starcraft, for instance, has different tech trees for each race, although each entry typically has a close analogue in another race (the Terran Goliath, Zerg Hydralisk, and Protoss Dragoon are all ground-based, ranged attack units). Age of Empires, on the other hand, has a single tech tree for all civilizations, but certain civilizations cannot access certain elements of it. This is compensated for with advances in other areas; so while the Egyptians cannot access advanced academy or siege units, they have bonuses for farming. This makes race selection much more tactical. Alternatively, Civilization allows all races to access the whole of the same tree, but different civilizations may be given certain technologies immediately.

External links

• Age of Wonders II tech trees: [1] [2]
• Civilization III tech trees for the ancient times, the Middle Ages, the Industrial Ages, and modern times
• StarCraft tech trees for Zerg, Protoss, and Terrans: [3]
• WarCraft III tech trees for humans, orcs, night elves, and undead