The choline basically adds polarity to our phospholipid bilayer. So we have the non polar fatty acid, the glycerol, that connects the fatty acids to our phosphate, the polar group, and then we have our choline. Now, instead of actually drawing out this entire molecule, we usually use a shortcut method of drawing our phospholipids, and that's this depiction here. So phospholipids can be described by using this pictorial image. We have this head, this spherical region that describes the phosphate as well as the choline, if we have that choline. So this is the polar region of our phospholipid.