Normals, Symetrical Models, etc

I generally don’t have my own internet access so I have to post my questions all at once when I do get a chance. Here’s a few things I’m stumped on.

A tutorial on blender mag had me mirror a robots face and then “recalculate normals” on it for, as far as I could see, making a clean seam between the left and right side of the face. I could not make it work right.

My two questions on this are “what does it mean to recalculate normals (what are normals anyway)” and “how is this done properly,” as I was evidently missing something on the tutorial.

Also, when I do mirror an image, how can I get the two sides to fuze together making one object completely connected in its vertices. Is this what recaluclating normals does?

Also, me being a photoshop user, how can I put photoshop to use in making highly detailed texture maps on animals such as lizards and insects? Idealy, I’d like to somehow export the “skin” and somehow know what’s being done to what part of the image as I work on it in photoshop. Or maybe I’m going in the wrong direction all together. Can I get some help in this one too?

Lastly, whats the best way to make tubes and wires in blender?

As always, your replies are appreciated.

Normals indicate the direction a face is pointing. F9 in Edit Mode under Mesh Tools you have a button to visualise them. If you apply a texture it will only be applied on the one side, that’s why it is important to know which way it is facing. Ctrl-N is the shortest way to make the normals point outward.

If you have to mirrored halves and you want to join them in Edit Mode - B for Box select vertices, the W key and choose remove doubles. Vertices on top of eachother will merge.

Photshop or any drawing program is great when you start learning about UV Mapping = Wrapping images around Meshes.

Tubes and wires can best be made with Bezier Curves and Bezier Circle, where BevOb: CurveCircle is typed in the menu of the F9 [Curve and surface] of the Curve.