The medieval Jewish sages placed a ban on eating legumes (kitniyot) on Passover, because they are similar in texture to chametz—even bread can be made out of their flour—so people might assume that if, for example, cornbread can be eaten on Passover, wheat or rye bread can be eaten too. This prohibition includes rice, beans and corn. This injunction was unanimously accepted by Ashkenazic Jews; many Sephardic Jews, however, continue to eat kitniyot on Passover. If you are Sephardic, speak to your rabbi to determine your family and community tradition.
The prohibition is only with regards to consumption of kitniyot; there is no obligation, however, to destroy or sell kitniyot products before Passover.