What is Pickle?
http://docs.python.org/library/pickle.html
Should I use Pickle?
Of course not.
* It is insecure. Untrusted pickles can do arbitrary things. For example, this pickle executes arbitrary Python expressions: pickle.loads("cbuiltin\neval\n(cbuiltin\nraw_input\n(S'py> '\ntRtR.")
* It is Python-only: pickles cannot be loaded in any other programming language / environment.
* It is schemaless (may be seen as a benefit sometimes)