I can click smooth shading or flat shading but it doesn’t specify.
I know I can choose from several in the materials tab but these only make a difference when rendering.
Is the 3d view smooth shading just some quick thing to display for 3d view, since every other renderer will replace it anyway?
Yes and no. ‘Yes’ because in viewport it’s indeed just a standard OpenGL smooth (Gouraud) shading. ‘No’ because you still need to specify whether (parts of) your model is (are) smooth-shaded or flat-shaded, because render engine will respect that and use corresponding normals to perform its magic. (edit: at least when Blender Render and Cycles are considered, I’m not sure about external engines).
Thanks, wonderful!
To be more specific, for the purpose of this question I make it all-or-none flat or smooth on my mesh.
I didn’t even realise I could smooth shade just parts of the mesh, thanks for teaching me that as well 
Yes, just to illustrate:
Smooth/Flat buttons in object mode apply the shading to the whole object. Partial shading is done in edit mode: select the faces you want to change shading on, W -> Shade Smooth or Shade Flat.
i would disagree with you guys
in edit mode you can smooth verts but this will change the verts locations to get a smooth surface
this is not a smooth function from a renderer / viewport point of view
the object smooth function does not change the verts location at all and it does it for the whole mesh
happy cycles
I am sorry RickyBlender, but you seem to be not paying attention to the discussion. ‘Shade Smooth’ and ‘Shade Flat’ do not change any positions for any vertices. They only flag the faces to be displayed/rendered using (interpolated) vertex normals or “flat” face normals, nothing more.
sorry i tought you were using the first one !
have to retest the Laplacian one too
that should also do some filtering if i remermber well which is sort of smoothing too!
happy cycles
