Amino acids in natural proteins are left-handed. They can be easily recognized: when the H atom is pointing towards the viewer the word 'CORN' can be read in a clockwise fashion.
The peptide bond is always planar, almost always trans (cis prolines occur once in a while). In all residues except for Gly the side chain severely limits the torsion angles about the CA atom. A good way to visualize the 'allowed torsion angles is the Ramachandran plot, discussed in section 5.4. Each of the torsion angles has a greek name:
1.2 Helices, Strands and Turns