Basic Building and Strategy of Starcraft II

• All races - beginning of game, build lots of probes/scv/ drones in the beginning, as much as possible 3/2/3 or 3/3/3 (probe / pylon / probe) (From Grandmasters)
  
• Build pylons, supply depots, overload so that you can build more probes/scvs/drones.
• Use speed building - chrono for Protoss
  
• Battle command for Terrans
• Spawn Larva with queens for Zerg