Introduction of BIW In BIW stands for body in white. It is nothing but sheet metal thin plates with stiffener. Main purpose of stiffener is to sustain load and increase strength of material strips. Once inner Biw structure ready then it will provide support to outer panels or we can say closure. The automotive body is made up of A,B,C pillars, body side panels, roof and doors. BIW knowledge is essential for every mechanical engineering students and professionals. It is just introduction, I will explain in detail/deep with my next article. Thanks everyone.