Camera Clipping Planes: Near and Far Meaning?

Dear community anyone can explain about " Near and Far " in Camera Clipping Planes?

On the documentation here
http://docs.unity3d.com/Manual/class-Camera.html
said
Near is The closest point relative to the camera that drawing will occur.
Far is The furthest point relative to the camera that drawing will occur.

If Near value is 0.3, what is does mean? 0.3 inc? 0.3 cm? 0.3 point?
If Far value is 1000, what is does mean? 1000 dm? 1000 cm? 1000 inc? 1000 point?

 

0.3 Unity Units and 1000 Unity Units.
Units are relative to whatever else is in your game.
If you have a model that's exported at 1.8m, then 1.8 Units should be 1.8m.
Therefore 1 Unit = 1m, in this case.

tl;dr. A unit is whatever you decide it to be.

 

Thanks for the explaination i'm a bit confused reading on documentation because no explaination on that page

 

It's distance. Stuff that is inside that distance range is visible. Units are anything you want, but the default is assumed (and basically standard) 1 unit = 1 meter.

 

As LaneFox said, objects further than the near clip plane and closer than the far clip plane will be rendered.
If you click on the Camera in your Scene, you should see the Camera's view frustum in the Scene View.
The closer to the camera, smaller side is the near clip plane, the further, larger one is the far clip plane.
Scrubbing the values of these in the Editor will allow you to see the changes.
To re-iterate, anything inside this frustum will be rendered, pending any culling.