Samsung 23 cu. ft. Smart Counter Depth 4-Door Flex™ refrigerator with Beverage Center and Dual Ice Maker in Black Stainless Steel Refrigerators – RF23A9671SG/AA | Samsung US

23 may refer to:

• 23 (number), the natural number following 22 and preceding 24
• one of the years 23 BC, AD 23, 1923, 2023

4 (four) is a number, numeral and digit. It is the natural number following 3 and preceding 5. It is a square number, the smallest semiprime and composite number, and is considered unlucky in many East Asian cultures.

Black is a color that results from the absence or complete absorption of visible light. It is an achromatic color, without hue, like white and grey. It is often used symbolically or figuratively to represent darkness. In Western society, black and white have often been used to describe opposites such as good and evil, the Dark Ages versus Age of Enlightenment, and night versus day. In Western society, since the Middle Ages, black has been the symbolic color of solemnity and authority, and for this reason it is still commonly worn by judges and magistrates.

Black was one of the first colors used by artists in Neolithic cave paintings. It was used in ancient Egypt and Greece as the color of the underworld. In Ancient Egypt, black had positive associations; being the color of fertility and the rich black soil flooded by the Nile. In the Roman Empire, it became the color of mourning, and over the centuries it was frequently associated with death, evil, witches, and magic. In the 14th century, it was worn by royalty, clergy, judges, and government officials in much of Europe. It became the color worn by English romantic poets, businessmen and statesmen in the 19th century, and a high fashion color in the 20th century. According to surveys in Europe and North America, it is the color most commonly associated with mourning, the end, secrets, magic, force, violence, fear, evil, and elegance.

Black is the most common ink color used for printing books, newspapers and documents, as it provides the highest contrast with white paper and thus is the easiest color to read. Similarly, black text on a white screen is the most common format used on computer screens. As of September 2019, the darkest material is made by MIT engineers from vertically aligned carbon nanotubes.

A door is a hinged or otherwise movable barrier that allows ingress (entry) into and egress (exit) from an enclosure. The created opening in the wall is a doorway or portal. A door's essential and primary purpose is to provide security by controlling access to the doorway (portal). Conventionally, it is a panel that fits into the doorway of a building, room, or vehicle. Doors are generally made of a material suited to the door's task. They are commonly attached by hinges, but can move by other means, such as slides or counterbalancing.

The door may be able to move in various ways (at angles away from the doorway/portal, by sliding on a plane parallel to the frame, by folding in angles on a parallel plane, or by spinning along an axis at the center of the frame) to allow or prevent ingress or egress. In most cases, a door's interior matches its exterior side. But in other cases (e.g., a vehicle door) the two sides are radically different.

Many doors incorporate locking mechanisms to ensure that only some people can open them (such as with a key). Doors may have devices such as knockers or doorbells by which people outside announce their presence. (In some countries, such as Brazil, it is customary to clap from the sidewalk to announce one's presence.) Apart from providing access into and out of a space, doors may have the secondary functions of ensuring privacy by preventing unwanted attention from outsiders, of separating areas with different functions, of allowing light to pass into and out of a space, of controlling ventilation or air drafts so that interiors may be more effectively heated or cooled, of dampening noise, and of blocking the spread of fire.

Doors can have aesthetic, symbolic, ritualistic purposes. Receiving the key to a door can signify a change in status from outsider to insider. Doors and doorways frequently appear in literature and the arts with metaphorical or allegorical import as a portent of change.

Ice is water that is frozen into a solid state, typically forming at or below temperatures of 0 °C, 32 °F, or 273.15 K. As a naturally occurring crystalline inorganic solid with an ordered structure, ice is considered to be a mineral. Depending on the presence of impurities such as particles of soil or bubbles of air, it can appear transparent or a more or less opaque bluish-white color.

Ice exhibits at least nineteen phases (packing geometries), depending on temperature and pressure. When water is cooled rapidly (quenching), up to three types of amorphous ice can form depending on its history of pressure and temperature. When cooled slowly, correlated proton tunneling occurs below −253.15 °C (20 K, −423.67 °F) giving rise to macroscopic quantum phenomena. In the Solar System, ice occurs naturally from as close to the Sun as Mercury to as far away as the Oort cloud objects. Beyond the Solar System, it occurs as interstellar ice, which is overwhelmingly amorphous. Yet, virtually all of the ice on Earth is of a hexagonal crystalline structure denoted as ice I_h (spoken as "ice one h").

The most common phase transition to ice I_h occurs when liquid water is cooled below 0 °C (273.15 K, 32 °F) at standard atmospheric pressure. Ice formed in this way is abundant on the Earth's surface, particularly in the polar regions and above the snow line, where it can aggregate from snow to form glaciers and ice sheets. As snowflakes and hail, ice is a common form of precipitation, and it may also be deposited directly by water vapor as frost. The transition from ice to water is melting and from ice directly to water vapor is sublimation. These processes plays a key role in Earth's water cycle and climate. In the recent decades, ice volume on Earth has been decreasing due to climate change. The largest declines have occurred in the Arctic and in the mountains located outside of the polar regions.

Humans have been using ice for various purposes for thousands of years. Some historic structures designed to hold ice to provide cooling are over 2,000 years old. Before the invention of refrigeration technology, the only way to safely store food without modifying it through preservatives was to use ice. Sufficiently solid surface ice makes waterways accessible to land transport during winter, and dedicated ice roads may be maintained. Ice also plays a major role in winter sports.

A refrigerator, colloquially fridge, is a commercial and home appliance consisting of a thermally insulated compartment and a heat pump (mechanical, electronic or chemical) that transfers heat from its inside to its external environment so that its inside is cooled to a temperature below the room temperature. Refrigeration is an essential food storage technique around the world. The low temperature lowers the reproduction rate of bacteria, so the refrigerator reduces the rate of spoilage. A refrigerator maintains a temperature a few degrees above the freezing point of water. The optimal temperature range for perishable food storage is 3 to 5 °C (37 to 41 °F). A similar device that maintains a temperature below the freezing point of water is called a freezer. The refrigerator replaced the icebox, which had been a common household appliance for almost a century and a half. The United States Food and Drug Administration recommends that the refrigerator be kept at or below 4 °C (40 °F) and that the freezer be regulated at −18 °C (0 °F).

The first cooling systems for food involved ice. Artificial refrigeration began in the mid-1750s, and developed in the early 1800s. In 1834, the first working vapor-compression refrigeration, using the same technology seen in air conditioners, system was built. The first commercial ice-making machine was invented in 1854. In 1913, refrigerators for home use were invented. In 1923 Frigidaire introduced the first self-contained unit. The introduction of Freon in the 1920s expanded the refrigerator market during the 1930s. Home freezers as separate compartments (larger than necessary just for ice cubes) were introduced in 1940. Frozen foods, previously a luxury item, became commonplace.

Freezer units are used in households as well as in industry and commerce. Commercial refrigerator and freezer units were in use for almost 40 years prior to the common home models. The freezer-over-refrigerator style had been the basic style since the 1940s, until modern, side-by-side refrigerators broke the trend. A vapor compression cycle is used in most household refrigerators, refrigerator–freezers and freezers. Newer refrigerators may include automatic defrosting, chilled water, and ice from a dispenser in the door.

Domestic refrigerators and freezers for food storage are made in a range of sizes. Among the smallest are Peltier-type refrigerators designed to chill beverages. A large domestic refrigerator stands as tall as a person and may be about one metre (3 ft 3 in) wide with a capacity of 0.6 m³ (21 cu ft). Refrigerators and freezers may be free standing, or built into a kitchen. The refrigerator allows the modern household to keep food fresh for longer than before. Freezers allow people to buy perishable food in bulk and eat it at leisure, and make bulk purchases.

Samsung Group (Korean: 삼성; Hanja: 三星; RR: samseong [samsʌŋ]; stylized as SΛMSUNG) is a South Korean multinational manufacturing conglomerate headquartered in Samsung Digital City, Suwon, South Korea. It comprises numerous affiliated businesses, most of them united under the Samsung brand, and is the largest South Korean chaebol (business conglomerate). As of 2020, Samsung has the world's eighth-highest brand value.

Samsung was founded by Lee Byung-chul in 1938 as a trading company. Over the next three decades, the group diversified into areas including food processing, textiles, insurance, securities, and retail. Samsung entered the electronics industry in the late 1960s and the construction and shipbuilding industries in the mid-1970s; these areas would drive its subsequent growth. Following Lee's death in 1987, Samsung was separated into five business groups – Samsung Group, Shinsegae Group, CJ Group and Hansol Group, and JoongAng Group.

Notable Samsung industrial affiliates include Samsung Electronics (the world's largest information technology company, consumer electronics maker and chipmaker measured by 2017 revenues), Samsung Heavy Industries (the world's second largest shipbuilder measured by 2010 revenues), and Samsung Engineering and Samsung C&T Corporation (respectively the world's 13th and 36th largest construction companies). Other notable subsidiaries include Samsung Life Insurance (the world's 14th largest life insurance company), Samsung Everland (operator of Everland Resort, the oldest theme park in South Korea) and Cheil Worldwide (the world's 15th largest advertising agency, as measured by 2012 revenues).