OCLC, Inc. doing business as OCLC, is an American nonprofit cooperative organization "dedicated to the public purposes of furthering access to the world's information and reducing information costs". It was founded in 1967 as the Ohio College Library Center became the Online Computer Library Center as it expanded. In 2017, the name was formally changed to Inc.. OCLC and its member libraries cooperatively produce and maintain WorldCat, the largest online public access catalog in the world. OCLC is funded by the fees that libraries have to pay for its services. OCLC maintains the Dewey Decimal Classification system. OCLC began in 1967, as the Ohio College Library Center, through a collaboration of university presidents, vice presidents, library directors who wanted to create a cooperative, computerized network for libraries in the state of Ohio; the group first met on July 5, 1967, on the campus of the Ohio State University to sign the articles of incorporation for the nonprofit organization and hired Frederick G. Kilgour, a former Yale University medical school librarian, to design the shared cataloging system.

Kilgour wished to merge the latest information storage and retrieval system of the time, the computer, with the oldest, the library. The plan was to merge the catalogs of Ohio libraries electronically through a computer network and database to streamline operations, control costs, increase efficiency in library management, bringing libraries together to cooperatively keep track of the world's information in order to best serve researchers and scholars; the first library to do online cataloging through OCLC was the Alden Library at Ohio University on August 26, 1971. This was the first online cataloging by any library worldwide. Membership in OCLC is based on use of services and contribution of data. Between 1967 and 1977, OCLC membership was limited to institutions in Ohio, but in 1978, a new governance structure was established that allowed institutions from other states to join. In 2002, the governance structure was again modified to accommodate participation from outside the United States.

As OCLC expanded services in the United States outside Ohio, it relied on establishing strategic partnerships with "networks", organizations that provided training and marketing services. By 2008, there were 15 independent United States regional service providers. OCLC networks played a key role in OCLC governance, with networks electing delegates to serve on the OCLC Members Council. During 2008, OCLC commissioned two studies to look at distribution channels. In early 2009, OCLC negotiated new contracts with the former networks and opened a centralized support center. OCLC provides bibliographic and full-text information to anyone. OCLC and its member libraries cooperatively produce and maintain WorldCat—the OCLC Online Union Catalog, the largest online public access catalog in the world. WorldCat has holding records from private libraries worldwide; the Online Computer Library Center acquired the trademark and copyrights associated with the Dewey Decimal Classification System when it bought Forest Press in 1988.

A browser for books with their Dewey Decimal Classifications was available until July 2013. Until August 2009, when it was sold to Backstage Library Works, OCLC owned a preservation microfilm and digitization operation called the OCLC Preservation Service Center, with its principal office in Bethlehem, Pennsylvania; the reference management service QuestionPoint provides libraries with tools to communicate with users. This around-the-clock reference service is provided by a cooperative of participating global libraries. Starting in 1971, OCLC produced catalog cards for members alongside its shared online catalog. OCLC commercially sells software, such as CONTENTdm for managing digital collections, it offers the bibliographic discovery system WorldCat Discovery, which allows for library patrons to use a single search interface to access an institution's catalog, database subscriptions and more. OCLC has been conducting research for the library community for more than 30 years. In accordance with its mission, OCLC makes its research outcomes known through various publications.

These publications, including journal articles, reports and presentations, are available through the organization's website. OCLC Publications – Research articles from various journals including Code4Lib Journal, OCLC Research, Reference & User Services Quarterly, College & Research Libraries News, Art Libraries Journal, National Education Association Newsletter; the most recent publications are displayed first, all archived resources, starting in 1970, are available. Membership Reports – A number of significant reports on topics ranging from virtual reference in libraries to perceptions about library funding. Newsletters – Current and archived newsletters for the library and archive community. Presentations – Presentations from both guest speakers and OCLC research from conferences and other events; the presentations are organized into five categories: Conference presentations, Dewey presentations, Distinguished Seminar Series, Guest presentations, Research staff presentations. Advocacy has been a part of OCLC's mission since its founding in 1967.

OCLC staff members meet and work with library leaders, information professionals, entrepreneurs, political leaders, trustees and patrons to advocate "advancing research, education, community de

Question answering is a computer science discipline within the fields of information retrieval and natural language processing, concerned with building systems that automatically answer questions posed by humans in a natural language. A question answering implementation a computer program, may construct its answers by querying a structured database of knowledge or information a knowledge base. More question answering systems can pull answers from an unstructured collection of natural language documents; some examples of natural language document collections used for question answering systems include: a local collection of reference texts internal organization documents and web pages compiled newswire reports a set of Wikipedia pages a subset of World Wide Web pagesQuestion answering research attempts to deal with a wide range of question types including: fact, definition, Why, semantically constrained, cross-lingual questions. Closed-domain question answering deals with questions under a specific domain, can exploit domain-specific knowledge formalized in ontologies.

Alternatively, closed-domain might refer to a situation where only a limited type of questions are accepted, such as questions asking for descriptive rather than procedural information. Question answering systems in the context of machine reading applications have been constructed in the medical domain, for instance related to Alzheimers disease Open-domain question answering deals with questions about nearly anything, can only rely on general ontologies and world knowledge. On the other hand, these systems have much more data available from which to extract the answer. Two early question answering systems were BASEBALL and LUNAR. BASEBALL answered questions about the US baseball league over a period of one year. LUNAR, in turn, answered questions about the geological analysis of rocks returned by the Apollo moon missions. Both question answering systems were effective in their chosen domains. In fact, LUNAR was demonstrated at a lunar science convention in 1971 and it was able to answer 90% of the questions in its domain posed by people untrained on the system.

Further restricted-domain question answering systems were developed in the following years. The common feature of all these systems is that they had a core database or knowledge system, hand-written by experts of the chosen domain; the language abilities of BASEBALL and LUNAR used techniques similar to ELIZA and DOCTOR, the first chatterbot programs. SHRDLU was a successful question-answering program developed by Terry Winograd in the late 1960s and early 1970s, it simulated the operation of a robot in a toy world, it offered the possibility of asking the robot questions about the state of the world. Again, the strength of this system was the choice of a specific domain and a simple world with rules of physics that were easy to encode in a computer program. In the 1970s, knowledge bases were developed; the question answering systems developed to interface with these expert systems produced more repeatable and valid responses to questions within an area of knowledge. These expert systems resembled modern question answering systems except in their internal architecture.

Expert systems rely on expert-constructed and organized knowledge bases, whereas many modern question answering systems rely on statistical processing of a large, natural language text corpus. The 1970s and 1980s saw the development of comprehensive theories in computational linguistics, which led to the development of ambitious projects in text comprehension and question answering. One example of such a system was the Unix Consultant, developed by Robert Wilensky at U. C. Berkeley in the late 1980s; the system answered questions pertaining to the Unix operating system. It had a comprehensive hand-crafted knowledge base of its domain, it aimed at phrasing the answer to accommodate various types of users. Another project was LILOG, a text-understanding system that operated on the domain of tourism information in a German city; the systems developed in the UC and LILOG projects never went past the stage of simple demonstrations, but they helped the development of theories on computational linguistics and reasoning.

Specialized natural language question answering systems have been developed, such as EAGLi for health and life scientists, Wolfram Alpha, an online computational knowledge engine that answers factual queries directly by computing the answer from externally sourced curated data. As of 2001, question answering systems included a question classifier module that determines the type of question and the type of answer. A multiagent question-answering architecture has been proposed, where each domain is represented by an agent which tries to answer questions taking into account its specific knowledge. Question answering is dependent on a good search corpus—for without documents containing the answer, there is little any question answering system can do, it thus makes sense that larger collection sizes lend well to better question answering performance, unless the question domain is orthogonal to the collection. The notion of data redundancy in massive collections, such as the web, means that nuggets of information are to be phrased in many different ways in differing contexts and documents, leading to two benefits: By having the right information appear in many forms, the burden on the question answering system to perform complex NLP techniques to understand the t

Gopal Baba Walangkar known as Gopal Krishna, is an early example of an activist working to release the untouchable people of India from their historic socio-economic oppression, is considered to be the pioneer of that movement. He developed a racial theory to explain the oppression and published the first journal targeted at the untouchable people. Gopal Baba Walangkar was born into a family of Mahar caste around 1840 at Ravdal, near Mahad in what is now Raigad district, Maharashtra, he was related to Ramabai, who in 1906 married B. R. Ambedkar. In 1886, after serving in the army, Walangkar settled at Dapoli and became influenced by another early social reformer, Jyotirao Phule, thus being a link between two of the most significant reform families of the period. Walangkar was appointed to the local taluk board of Mahad in 1895, which displeased the members from the upper castes and caused considerable debate in newspapers, he died at Ravdal in 1900. The Aryan invasion theory, since discredited, was in vogue at this time.

Walangkar extended Phule's version of this racial theory, that the untouchable people of India were the indigenous inhabitants and that the Brahmin people were descended from Aryans who had invaded the country. Walangkar claimed that "high-caste people from the south were'Australian–Semitic non-Aryans' and African negroes, that Chitpavan Brahmans were'Barbary Jews', that the high-caste Marathas' forebears were'Turks'". In 1888, Walangkar began publishing the monthly journal titled Vital-Vidhvansak, the first to have the untouchable people as its target audience, he wrote articles for Marathi-language newspapers such as Sudharak and Deenbandhu, as well as composing couplets in Marathi that were intended to inspire the people. Having read Hindu religious texts, Walangkar concluded that caste was contrived by the Aryan invaders to control the Anaryans. In 1889, he published Vital Viduvansan, which protested the position of untouchables in society and raised consciousness regarding what those people should expect.

He addressed this pamphlet, crafted as a collection of 26 questions, to the elites of Maharashtrian society. T. N. Valunjkar says that Walangkar "can be regarded as the first intellectual rebel from the dalit community to have launched a scathing criticism of the caste system and the position of dalits in it." Nonetheless, his criticism was intended to cause change through an appeal to those elites, rather than an opposition to them. It was an awareness-raising style, in the hope that the paternalist elements of society would take heed but it warned that the untouchables might leave India unless their situation improved. A further significant work, titled Hindu Dharma Darpan, appeared in 1894. Walangkar at once empowered the Mahars and diminished the influence of Brahmin priests by forming a group of Mahar astrologers to set the times for religious ceremonies, the only service that Brahmins had been willing to perform for the caste. Walangkar founded the Anarya Dosh-Parihar Mandali; some sources say this took place in the same year that he left the army but Anand Teltumbde gives 1890 as the date and suggests it was connected with an issue relating to military recruitment.

The Mahar were heavily recruited into British military units, but this process slowed after the Indian Rebellion of 1857. Their recruitment was halted under Lord Kitchener in the early 1890s. Before the rebellion, Mahar regiments made up one-sixth of the Bombay units of the British East India Company but thereafter they were pensioned off and removed from military service. Mahar recruitment reached its nadir in the early 1890s when Kitchener halted the recruitment of untouchables in Maharashtra in favour of "martial races," such as the Marathas and other north-western communities; the Mahar community attempted to confront this block with a petition circulated among the Mahar and Mang former soldiers—all Marathi-speaking untouchables—but the movement was unable to organise and submit their petition. It was Walangkar, through the Anarya Dosh-Parihar Mandali. Walangkar is considered to be the pioneer of the Dalit movement, despite the work of Harichand Thakur through his Matua organisation involving the Namasudra community in Bengal Presidency.

Ambedkar himself believed Walangkar to be the progenitor