For which surfaces, is a spirit level used for testing straightness ?

Explanation

Concept: Spirit Level: Spirit level, bubble level, or simply a level is an instrument design to indicate whether a surface is horizontal (level) or vertical (plumb). Important Points There are different types of spirit level for different uses: Surveyor’s leveling instrument Carpenter’s level (either wood, aluminum or composite materials) Mason’s level Torpedo level Post level Line level Engineer’s precision level Electronic level Inclinometer Slip or Skid indicator Bull’s eye level