Many mugs are made of ceramic materials such as earthenware, bone china, porcelain or stoneware. Some are unreal from strengthened glass, such as Pyrex. Other materials, including plastic, embolden and enameled metal are accustomed where break resistance is at a premium, such as for campers. Techniques such as satiny screen printing or decals Photo Mugs can be used to apply decorations; these are fired onto the mug to ensure permanence.
A travel mug is a variation on the traditional mug that is exceeding for transporting hot liquids. It may or may not be a vacuum flask, but is mostly well insulated and completely enclosed, with an easily closed opening on the top.