Metal roof provides increased wind resistance when compared to other roofing materials. This is because metal roofing systems use interlocking panels. The disadvantages of metal roofs include the noise created from rain hitting the roof, and, in snowy areas, the tendency of snow to easily fall off the roof and onto pedestrians or property. Originally, metal roofs were made of corrugated galvanized steel: a wrought iron–steel sheet was coated with zinc and then roll-formed into corrugated sheets. Another approach is to blend zinc, aluminum, and silicon-coated steel. These products are sold under various trade names like "Zincalume" or "Galvalume". The surface may
What Is Art? What Is Art? What is Art? ( "Chto takoye iskusstvo?") is a book by Leo Tolstoy. It was completed in Russian in 1897 but first published in English due to difficulties with the Russian censors. Tolstoy cites the time, effort, public funds, and public respect spent on art and artists as well as the imprecision of general opinions on art as reason for writing the book. In his words, "it is difficult to say what is meant by art, and especially what is good, useful art, art for the sake of which we might condone such sacrifices as are being