A shed is typically a simple, single-story roofed structure in a back garden or on an allotment that is used for storage, hobbies, or as a workshop. Sheds vary considerably in their size and complexity of construction, from simple open-sided ones designed to cover bicycles or garden items to large wood-framed structures with shingled roofs, windows, and electrical outlets. Sheds used on farms or in industry can be large structures. The main types of shed construction are metal sheathing over a metal frame, plastic sheathing and frame, all-wood construction (the roof may be asphalt shingled or sheathed in tin), and vinyl-sided sheds built over a wooden frame. Small sheds may include a wooden or plastic floor, while more permanent ones may be built on a concrete pad or foundation. Sheds may be lockable to deter theft or entry by children, domestic animals, wildlife, etc. A culture of shed enthusiasts exists in several countries for people who enjoy building sheds and spending time in them for relaxation. In Australia and New Zealand there are magazines called The Shed, an association for shed hobbyists (the Australian Men's Shed Association), and a book entitled Men and Sheds. In 2020 the company Shed Hub was created as a platform for shed enthusiasts to learn about products and to foster a culture around sheds in the United States .