* Aluminum cans are the most common type. They are lightweight, recyclable, and resistant to corrosion.

* Steel cans are often used for food items that need to be heated, like soups and beans. They are strong, durable, and also recyclable.

There are some variations within these materials, but these are the most common:

* Aluminum: Most aluminum cans are made from aluminum alloys, which are mixtures of aluminum with other metals like magnesium and manganese. These alloys make the aluminum stronger and more resistant to damage.

* Steel: Steel cans can be made from tin-plated steel, which is a thin layer of tin applied to a steel base. Tinplating helps to prevent corrosion and make the can more resistant to rusting.

It's important to note that both aluminum and steel cans are recyclable. This makes them an environmentally friendly option compared to other packaging materials.