There are many misconceptions and misrepresentations about evolution.
The five propositions below seem to be the most common misconceptions based on a Creationist straw-man version of evolution. If you hear anyone making any of them, chances are excellent that they don't know enough about the real theory of evolution to make informed opinions about it.
1. Evolution has never been observed.
2. Evolution violates the 2nd law of thermodynamics.
3. There are no transitional fossils.
4. The theory of evolution says that life originated, and evolution proceeds, by random chance.
5. Evolution is only a theory; it hasn't been proved.
Most are promulgated by fundamentalist Christians, i.e. "Creationists" who take the six day Creation literally or "Intelligent Design" proponents who believe that all flora and fauna were created in one fell swoop by God although not necessarily in six days.
To really see how misguided people are with respect to evolution, view the list of misconceptions developed by the University of California Museum of Paleontology @ http://evolution.berkeley.edu/evolibrary/misconceptions_faq.php
and the excellent explanation explanation of evolution compiled by the National Center for Science Education with funding from the National Science Foundation @ http://ncseweb.org/