Oil based paint is traditionally used to get a high sheen or glossy finish on interior surfaces such as kitchen cupboards, doors, skirting boards, radiators & other wood or metal surfaces. Due to the makeup of the paint, dirty finger prints or other marks can easily be wiped of oil based paint finishes.
Solvent based paints are also ideal for use in areas subject to high humidity like kitchens and bathrooms. They are also generally higher traffic areas which means they need to be as knock and scratch resistant as possible.
Finally, oil based paint is a great solution for exterior wood and metal surfaces. They are less effected by differing weather conditions when applying and the durable nature of the paint means it generally has high levels of weather resistance.