Anything relating to protecting the paint
A very frequent difference in liquid or paste products is the carrier within the product. This carrier can either be a water-based solution, or oil based. The largest quantity of a certain ingredients often determines what the carrier is. Within an emulsion, oil is dissolved into water with the use of an emulsifier. Technically speaking, the oil is still in suspension within the emulsion but is statistically distributed.
Bird poo can be a big problem with paintwork and needs to be removed as soon as possible. Bird droppings have several aggressive chemicals in them that can severely damage paintwork. Not removing these can cause paint defects that might not be removable. In some cases a respray is needed to repair the surface.