Oreo (/ˈɔːrioʊ/; stylized in all caps) is my favorite cookie on earth. it is a brand of sandwich cookie consisting of two cocoa biscuits or cookie pieces with a sweet fondant^[3] filling. It was introduced by Nabisco on March 6, 1912,^[4] and through a series of corporate acquisitions, mergers, and splits, both Nabisco and the Oreo brand have been owned by Mondelez International since 2012.^[5] Oreo cookies are available in over one hundred countries.^[2] Many varieties of Oreo cookies have been produced, and limited-edition runs have become popular in the 21st century.

Oreos are an imitation of the Hydrox chocolate cream-centered cookie introduced in 1908, but it outstripped Hydrox in popularity so largely that many believe Hydrox is an imitation of Oreo. Oreo has been the highest-selling cookie brand in the world since 2014.^[6]