bar, the, originally, the rail that enclosed the judge in a court; hence, a court or a system of courts. The persons qualified and authorized to conduct the trial of cases are also known collectively as "the bar." From late medieval times in England the Inns of Court acted as training schools for men who were to plead causes in the courts, and when a student was judged to be trained in competence, he was "called to the bar" of the Inn; automatically he was then judged competent to plead at the bar of the courts. Modern bar associations, through which the legal profession regulates itself, derive from the Inns of Court. Attorneys must be admitted to the bar before they can practice law in the United States. The requirements for admission vary among the states, but generally an applicant must be of good moral character, have completed a stated course of study at a law school, and have passed a bar examination. The last two requirements were once satisfied by clerking and "reading law" with a practicing attorney. A lawyer can be prohibited from practicing law (disbarred) for conduct impeding justice, criminal acts involving moral turpitude, or unethical professional conduct. The first state to allow women admission to the bar was Iowa (1869), and Great Britain admitted women to law practice in 1919. There are 180 American Bar Association-approved law schools in the United States, the oldest being Harvard Law School, founded in 1817.

bar code, computer coding system that uses a printed pattern of lines or bars to identify products, mail and packages, customer accounts, and the like. Bar codes are read by optically scanning the printed pattern and using a computer program to decode the pattern. In a linear bar code system, the code itself contains no information about the item to which it is assigned but represents a string of identifying numbers or letters. When the code is read by an optical scanner linked to a computer, the computer can provide and record information about the item, such as its price or the quantity sold, from and to databases.

The original North American Universal Product Code (UPC), which dates to 1971, used a set of two dark (usually black) and two light (usually white) bars of specified thicknesses to represent 12 numbers, but beginning in 2005 the Uniform Code Council, now known as GS1 US, adopted the similar European Article Numbering Code (EAN), which encodes 13 numbers and had become the international standard. The standards for the international product bar code system are managed by GS1, formerly known as EAN International, which is based in Brussels. The dark bars may be from one to three units wide and the light bars from one to four units. For registration purposes two one-unit dark bars are placed at each end and in the middle. Each item is assigned a unique numeric code, which is printed as a bar code on the item's packaging.

So-called two-dimensional (2D) bar codes permit the encoding of information about an item in addition to an identifying code. In a 2D bar code, two axes, or directions, are used for recording and reading the codes and the bar size is reduced, increasing the space available for data in the way that a column of words improves on a column of letters. Some 2D codes do not use bars at all, such as the United Parcel Service's hexagon-based Maxicode.

An emerging technology, radio-frequency identification (RFID), could supplant the bar code in most applications. The newer radio-based devices overcome many of the limitations inherent in the bar code's optical technology.

bar, offshore: see beach.

Potter's Bar, town (1991 pop. 22,755), Hertfordshire, central England, in the Midlands. Potter's Bar is a residential district, most of which is within the Green Belt Zone barred to industrial development. An aircraft museum is within the 17th-century Salisbury House.

Bar-le-Duc, town (1990 pop. 18,577), capital of Meuse dept., NE France, in Lorraine. It has textile mills, iron foundries, printing plants, and metallurgical and food-processing industries. Situated in the picturesque Ornain valley, Bar-le-Duc has preserved many old houses (16th, 17th, and 18th cent.). It has a 15th-century church and one from the 13th and 14th cent. It was the capital of the county (later duchy) of Bar, an irregularly shaped area stretching from the Marne to the Luxembourg frontier. The duchy passed (15th cent.) to René of Anjou, later also duke of Lorraine. Bar thereafter shared the history of Lorraine, with which it passed to France in 1766.

Bar-jesus, called Elymas, in the New Testament, Jewish sorcerer at Paphos who tried to divert a prospective Christian convert and was cursed with blindness.

Bar-Hebraeus, Gregorius, 1226-86, Syrian scholar, bishop of the Jacobite Church. Partly Jewish in ancestry, his original name was Abu-al-Faraj. His most celebrated work is a chronicle in Syriac of the world from Adam down. His commentaries (in Arabic and Syriac) on Aristotle were widely known among Arabic-speaking scholars.

Bar, Confederation of, union formed in 1768 at Bar, in Podolia (now in W Ukraine), by a number of Polish nobles to oppose the interference of Catherine II of Russia in Polish affairs. Headed by the Pulaski family and supported by the Roman Catholic clergy, it sought to defend Polish independence, the Polish constitution, the rights of the landed gentry, and Roman Catholicism. Further, it endeavored to impose Roman Catholicism, as opposed to Orthodox Eastern beliefs, on the serfs of right-bank Ukraine (W of the Dnieper), which was then under Polish rule. Working against the confederation's policies was the Polish king, Stanislaus II, whose election (1764) had been sponsored by Catherine and who at her request had conceded to non-Catholics the rights of freedom of worship and participation in the Polish government. Incensed by the confederation's hostile intentions toward them, the right-bank Ukrainians rose up (1768) in the rebellion of the Koliyivshchyna (see Ukraine). Catherine sent Russian forces to suppress the rebellion, however, in the fear that it might spread among serfs under her control. In 1770 the confederation declared King Stanislaus deposed. Supported to a minor degree by France and more effectively by the Ottoman Empire, which declared war on Catherine, the confederation fought a bitter war against Russia until 1772, when its effective resistance was ended by the first partition of Poland (see Poland, partitions of).

Bar Mitzvah [Aramaic,=son of the Commandment], Jewish ceremony in which the young male is initiated into the religious community, according to tradition at the age of 13 years and a day. The celebrant performs his first act as an adult, saying the blessing for the reading in the synagogue of part of the weekly portion of the Torah or, more traditionally, performing the actual reading. The exact content of the ceremony varies according to local traditions and customs (e.g., Ashkenazic or Sephardic). Today the religious ceremony is accompanied by a social celebration that is considered a Seudat Mitzvah, a feast in celebration of the fulfillment of a commandment. The 20th cent. has seen the introduction (1922) of the Bas, or Bat, Mitzvah, a comparable ceremony for the young female, by the Reform, Conservative, and Reconstructionist groups and to a much lesser extent by the Orthodox. The Bat Mitzvah ceremony is performed at the age of 12 or 13. It often includes the reading of the weekly Haftarah, although it is increasingly becoming identical with the Bar Mitzvah.

Bar Kokba, Simon, or Simon Bar Cochba [Heb.,=son of the star], d. A.D. 135, Hebrew hero and leader of a major revolt against Rome under Hadrian (132-135). He may have claimed to be a Messiah; the Talmud relates that Akiba ben Joseph credited him with this title. His personality and the facts of his life are surrounded by legend. He is sometimes called Simon the Prince of Israel. At first he successfully defeated the Roman armies, but the tide turned against him with the victories of the Roman general Julius Severus, and he was killed at Bether. Israeli archaeologists have found a number of letters in his handwriting.

Bar Harbor, town (1990 pop. 2,768), SE Maine, on Mount Desert Island and on Frenchman Bay; settled 1763, inc. 1796. It was a famed New England resort during the 19th cent. Bar Harbor is a port of entry, with ferry connections to Yarmouth, N.S., during the summer. In 1947 a large part of the town was destroyed by fire. Jackson Memorial Laboratory for biological research and the College of the Atlantic are there. Nearby Acadia National Park is a major tourist attraction.

Bar Cochba, Simon: see Bar Kokba, Simon.

American Bar Association (ABA), voluntary organization of lawyers admitted to the bar of any state. Founded (1878) largely through the efforts of the Connecticut Bar Association, it is devoted to improving the administration of justice, seeking uniformity of law throughout the nation, and maintaining high standards for the legal profession. It is composed of over 30 committees that deal with such diverse legal topics as maritime law, professional ethics, legal education, the judicial system, and legal aid for the indigent. Through its main office in Chicago, the ABA coordinates the activities of state and local bar associations. In 1999 its membership exceeded 404,000. Affiliated organizations include the American Law Student Association and the American Bar Foundation, a group devoted to legal research and education.

Rod or bar that resists twisting (see torque) and has a strong tendency to return to its original position when twisted. In an automobile, a torsion bar is a long spring-steel element with one end held rigidly to the frame and the other end twisted by a lever connected to the axle. It thus provides a spring action for the vehicle.

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Event in men's gymnastics competition in which a steel bar fixed about 8 ft (2.4 m) above the floor is used for swinging exercises. Competitors generally wear hand protectors and perform routines that last 15–30 seconds. Exercises include the giant swing and various vaults (such as the straddle vault). It has been an Olympic event since the first modern Olympic Games in 1896.

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Printed series of parallel bars of varying width used for entering data into a computer system, typically for identifying the object on which the code appears. The width and spacing of the bars represent binary information that can be read by an optical (laser) scanner that is part of a computer system. The coding is used in many different areas of manufacturing and marketing, including inventory control and tracking systems. The bar codes printed on supermarket and other retail merchandise are those of the Universal Product Code (UPC).

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Group of lawyers organized primarily to deal with issues affecting the legal profession. In general, they are concerned with furthering the interests of lawyers through advocating reforms in the legal system, sponsoring research projects, and regulating professional standards. Bar associations sometimes administer the examinations required for admission to practice law. The largest U.S. bar association is the American Bar Assn.

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Jewish ritual celebrating a boy's 13th birthday and his entry into the community of Judaism. It usually takes place during a Sabbath service, when the boy reads from the Torah and may give a discourse on the text. The service is often followed by a festive Kiddush and a family dinner on the same day or next day. Reform Judaism substituted confirmation of boys and girls for the Bar Mitzvah celebration after 1810, but many congregations restored the Bar Mitzvah in the 20th century. A separate ceremony for girls, Bat Mitzvah, has been instituted in Reform and Conservative Judaism.

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Voluntary association (founded 1878) of U.S. lawyers, judges, and other legal professionals. The largest bar association in the U.S., it seeks to improve the legal profession, ensure the availability of legal services to all citizens, and improve the administration of justice. It conducts educational and research projects, sponsors professional meetings, and publishes a monthly journal. At the beginning of the 21st century its membership exceeded 400,000.

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