While the two are mostly used interchangeably, they do not mean the same. Cassava flour is made from the roots of the cassava plant, which is peeled, dried, and ground into flour. Tapioca, on the other hand, refers to cassava starch. Simply put, tapioca is the starchy remains from the cassava root which is obtained through washing and pulsing, resulting in a liquid that is then evaporated to leave behind tapioca.