Default Tags and Layers in Unity

So when you first pull up Unity it has 6 default tags

  • Respawn
  • Finish
  • Editor Only
  • Main Camera
  • Player
  • Game Controller

and 4 default layers (not including the 4 un-named ones unity predefines)

  • Default
  • TransparentFX
  • Ignore Raycast
  • Water

Do these layers and tags have specific purposes that are unique or are they are just ones people usually use so they included them for convenience? If they are special how so? Thanks in advance.

Main Camera: an object tagged this will respond to Camera.main.

Editor Only: an object tagged this will not appear in a build.

TransparentFX: lens flares will show through the collider of an object on this layer.

Ignore Raycast: an object on this layer will be ignored by raycasts (including OnMouseOver, etc.).