Terrain and Cover

All rules references

Terrain

Difficult TerrainEach square costs 5 extra feet of movement.
Greater Difficult TerrainEach square costs 10 extra feet of movement.
Hazardous TerrainMoving through hazardous terrain deals damage.
Narrow SurfaceOff-guard and must Balance to cross. When you're hit or fail a save, succeed at a Reflex save or fall.
Uneven GroundOff-guard and might need to Balance or fall prone. When you're hit or fail a save, succeed at a Reflex save or fall.
InclineYou need to Climb to ascend an incline. You're off-guard while Climbing.

Cover

Draw a line from the center of the attacker's space or burst to the center of the target's space.

Type of CoverBonusCan Hide
Lesser Cover+1 circumstance bonus to AC if line passes through creatures but no objects.No
Cover (Standard)+2 circumstance bonus to AC, Reflex saves against area effects, and Stealth checks to Hide or Sneak. You can use Take Cover to increase this to greater cover.Yes
Greater CoverAs cover, but a +4 bonus.Yes

Section: Playing the GamePathfinder Player Core pg. 423-424