The sky is blue.

 

 

That is all .

 

 

Holy crap, no way, you're lying.

 

I just looked out my window, you're right! This is amazing!

Who needs the sky when you got a roof?

actually the sky is rainbow

 

it just looks blue to us

It's purple for me. You people have a strange sky color. 

Technically, the sky is not blue and this is only the way you process it.  You process it as blue because blue is the most scattered color by the atmosphere and so that's most of the colors you see.  It has all the colors, though.

where did you hear such blasphemy

 

the sky is frickin purple

No colors anymore I want to paint them black.