StarCraft/Buildings

Overview
Players have many ways of constructing structures. The fastest method is to use the hotkeys B for Build and V for Advanced Build, then pressing the associated hotkey for a particular structure while hovering the mouse near the prospected building site.

Buildings take a rather short time to build, and are rather cheap compared to units. Therefore players generally build ample buildings. Another reason of doing this is use as backup. If an enemy destroys a Protoss Gateway, for example, the player cannot build Gateway associated units nor travel up the tech tree for about another crucial minute (until a Gateway is rebuilt) UNLESS the player has at least one that was not destroyed.

Building locations are also crucial, as they may determine the ease or difficulty of bypassing units-either moving your units from one front to another or to prevent enemies from simply running past defensive structures. Buildings can be used to protect a Terran Siege Tank in Siege Mode as well as grant it extra range; enemies attacking it would be outside the 'too close' range. Meanwhile, the same buildings could block a Reaver's attack pathway or at least slow down its rate of fire.

Defensive structures should be placed at chokepoints for maximum effectiveness and should be spread out throughout the base-especially at resource nodes-to defend against enemy infiltrations and provide response time for your units.

Zerg and Creep
The Zerg is the only race that cannot build defensive structures at expansion points before beginning the construction of a Hatchery at that location. Therefore, players must defend their hopeful expansion points with an adequate supply of troops.

Creep can be a very limiting factor, but constantly trying to expand it will economically ruin a Zerg player, primarily because the creep does not DO anything. Instead of building a tangle of Creep Colonies, players should concentrate on growing Hatcheries, forming hatchery clusters at their main base. The advantage of doing so is that players have ample unit-constructing facilities for when their expansions finally begin to turn a profit.

Defensive Structure Placement
The Terrans have the least need for defensive structures, because generally a defense will include units such as a Siege Tank that cannot be defended with a Bunker. By the time an enemy has destroyed everything outside the Bunkers, the paltry resistance of Marines and Firebats will not save a base or expansion.

Zerg players turn almost all creep colonies into their derivatives, because doing so only costs an additional 75 Minerals, compared to the 150 for a Photon Cannon.