Fatty acids can either be saturated or unsaturated. If they are saturated, they stack easily and form solids at room temperature. If they are unsaturated, however, double bonds are introduced, and these double bonds introduce kinks into the structure of the fatty acid molecule. In a different question on this site, it was suggested that the reason why double bonds cause kinks to form is that they interrupt the zig zag shape of the molecule.
However, what was left unexplained is how double bonds interrupt the zig zag shape. If we were dealing with a cis fatty acid, and both hydrogens were located on top, why would this lead to a kink?