A tin can, tin (especially in British English), steel can, or a can, is an air-tight container for the distribution or storage of goods, composed of thin metal, and requiring cutting or tearing of the metal as the means of opening. Cans hold diverse contents, but the overwhelming majority preserve food by canning.

"Tin" cans are made of tinplate which is tin-coated steel. Cans may also be made of aluminium or other metals.Most cans have identical and parallel round tops and bottoms with vertical sides. However, where the small volume to be contained and/or the shape of the contents suggests it, the top and bottom may be rounded-corner rectangles  or ovals. Other contents may justify a can that is overall somewhat conical in shape.

Red is any of a number of similar colors evoked by light consisting predominantly of the longest wavelengths of light discernible by the human eye, in the wavelength range of approximately 630–700 nm.  Longer wavelengths than this are called infrared, or below red and cannot be seen by human eyes.

Red's wavelength has been an important factor in laser technologies as red lasers, used in early compact disc technologies, are being replaced by blue lasers, as red's longer wavelength causes the laser's recordings to take up more space on the disc than blue lasers. A main theory for why primates developed sensitivity to red, is that it allowed ripe fruit to be distinguished from unripe fruit and inedible vegetation. This further drove other adaptations to take advantage of this new ability, such as red faces. Red light is also used to preserve night vision in low-light or night-time situations, as the rod cells in the human eye aren't sensitive to red. Red is one of the three additive primary colors of light, complementary to cyan, in RGB  color systems. Red is also one of the three subtractive primary colors of RYB color space but not CMYK color space.