What is the difference between a "realist" and "optimist"...?

i wud say....a 'realist' is a person who sees d world as it is.....not marred by his own perceptions.....this is quite in contrast 2 a person who is 'optimistic'.....he wud see only d +ve aspects f life.....may hope against al hopes in situations.....this can b misleading n fatal........a person shud b optimistic for sure.....bt nt beyond d realities f life....a person whose vision is fogged by false hopes plans on d errored base.......