Build order

In strategy computer games, of both the turn-based and real-time varieties, a build order is a linear pattern of production, research, and resource management aimed at achieving a specific and specialized goal. They are analogous to chess openings, in that a player will have a specific order of play in mind, however the amount the build order, the strategy around which the build order is built or even which build order is then used varies on the skill, ability and other factors such as how aggressive or defensive each player is.

Often, the name of a build order usually reflects two key aspects therein:

Evidence of this can be found in the following examples:

Strategy computer games typically offer a player many choices in which structures to build, units to train, and which 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. A tech tree is the representation of all possible paths of research a player can take. Analysis of the tech tree leads to specific paths that a player can take to optimally advance specific strategic or tactical goals. These optimized paths are build orders.

For example, a player who plans to launch an attack by air may only build the structures necessary to construct air units and may research only the technologies which enhance the capabilities of air units. The order in which to build those structures and research those technologies is known as a build order. The same player could instead choose a slightly different build order that goes for air units but also creates a small ground-defense army – this would be a more defensive, less risky choice at the expense of having maximum airspace power.

As you can see in the list above build orders are usually used to determine how a player will start the game, which is why they are often miscalled "openings". There are many reasons for this: a flawed game start could mean that you lose the game early on, so it is important to have resilient openings; how you start a match most often than not narrows the middle and late-game options so the very first few choices alone dictate your future options; middle and late game choices require you to study the current situation so not only are they harder to plan ahead but then one also has more time to think, while on the very beginning it is more advantageous to have a fixed plan and execute it as fast and precisely as possible. Build orders can also plan ahead for late-game scenarios but that is less common.

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Wikipedia