Aluminium or aluminum is a chemical element with symbol Al and atomic number 13. It is a silvery-white, soft, nonmagnetic and ductile metal in the boron group. By mass, aluminium makes up about 8% of the Earth's crust; it is the third most abundant element after oxygen and silicon and the most abundant metal in the crust, though it is less common in the mantle below. The chief ore of aluminium is bauxite. Aluminium metal is so chemically reactive that native specimensare rare and limited to extreme reducing environments. Instead, it is found combined in over 270 different minerals.
Aluminium is remarkable for its low density and its ability to resist corrosion through the phenomenon of passivation. Aluminium and its alloys are vital to the aerospace industry and important in transportation and building industries, such as building facades and window frames. The oxides and sulfates are the most useful compounds of aluminium.
Despite its prevalence in the environment, no known form of life uses aluminium salts metabolically, but aluminium is well tolerated by plants and animals. Because of these salts' abundance, the potential for a biological role for them is of continuing interest, and studies continue.
Box (plural: boxes) describes a variety of containers and receptacles for permanent use as storage, or for temporary use, often for transporting contents.
Boxes may be made of durable materials such as wood or metal, or of corrugated fiberboard, paperboard, or other non-durable materials. The size may vary from very small (e.g., a matchbox) to the size of a large appliance. A corrugated box is a very common shipping container. When no specific shape is described, a box of rectangular cross-section with all sides flat may be expected, but a box may have a horizontal cross section that is square, elongated, round or oval; sloped or domed top surfaces, or vertical edges.They are not always made up of squares.
Decorative or storage boxes may be opened by raising, pulling, sliding or removing the lid, which may be hinged and/or fastened by a catch, clasp, or lock.
A newspaper is a periodical publication containing written information about current events.
Newspapers can cover a wide variety of fields such as politics, business, sports and art, and often include materials such as opinion columns, weather forecasts, reviews of local services, obituaries, birth notices, crosswords, editorial cartoons, comic strips, and advice columns.
Most newspapers are businesses, and they pay their expenses with a mixture of subscription revenue, newsstand sales, and advertisingrevenue. The journalism organizations that publish newspapers are themselves often metonymically called newspapers.
Newspapers have traditionally been published in print (usually on cheap, low-grade paper called newsprint). However, today most newspapers are also published on websites as online newspapers, and some have even abandoned their print versions entirely.
Newspapers developed in the 17th century, as information sheets for businessmen. By the early 19th century, many cities in Europe, as well as North and South America, published newspapers.
Some newspapers with high editorial independence, high journalism quality, and large circulation are viewed as newspapers of record.