Alpha helices and beta sheets are two common secondary structures found in proteins.
Alpha helices are formed by hydrogen bonds between residues, with the side-chain groups projecting outwards. They are able to have charged and uncharged sides, or hydrophobic and hydrophilic sides, by controlling the order of residues - this is seen in leucine zipper proteins, where every seventh residue is a leucine residue. This gives a positive charge to one side of the protein, allowing it to bind specifically to the negatively charged DNA.
Beta sheets are formed of individual beta strands. These antiparallel strands allow the formation of a flat sheet, which can be amphipathic. The side chains project on alternating sides.