Download: Discovery Studio Visualizer
Discovery Studio Visualizer 3.0 is a free commercial-grade graphics visualization tool for viewing, sharing, and analyzing protein and modeling data. This program is used in some chemistry classes at GSU.
There are a variety of free and open source molecular graphics visualization programs that can be used for exploring biological macromolecule structures (i.e., proteins, nucleic acids and other small molecules such as those found in the Protein Data Bank (PDB).
A few examples include:
The Protein Data Bank offers a page of molecular graphics links here.