International Olympiad in Informatics
The International Olympiad in Informatics is an annual competitive programming competition for secondary school students. It is the second largest olympiad, after International Mathematical Olympiad, in terms of number of participating countries; the first IOI was held in 1989 in Bulgaria. The contest consists of problem-solving of algorithmic nature. To deal with problems involving large amounts of data, it is necessary to have not only programmers, "but creative coders, who can dream up what it is that the programmers need to tell the computer to do; the hard part isn't the programming, but the mathematics underneath it." Students at the IOI compete on an individual basis, with up to four students competing from each participating country. Students in the national teams are selected through national computing contests, such as the Australian Informatics Olympiad, British Informatics Olympiad, Indian Computing Olympiad or Bundeswettbewerb Informatik; the International Olympiad in Informatics is one of the most prestigious computer science competitions in the world.
UNESCO and IFIP are patrons. On each of the two competition days, the students are given three problems which they have to solve in five hours; each student works on his/her own, with only a computer and no other help allowed no communication with other contestants, books etc. To solve a task the contestant has to write a computer program and submit it before the five-hour competition time ends; the program is graded by being run with secret test data. From IOI 2010, tasks are divided into subtasks with graduated difficulty, points are awarded only when all tests for a particular subtask yield correct results, within specific time and memory limits. In some cases, the contestant's program has to interact with a secret computer library, which allows problems where the input is not fixed, but depends on the program's actions – for example in game problems. Another type of problem has known inputs which are publicly available during the five hours of the contest. For these, the contestants have to submit an output file instead of a program, it is up to them whether they obtain the output files by writing a program, or by hand, or by a combination of these means.
Pascal will have been removed as an available programming language by 2019.:11IOI 2010 for the first time had a live web scoreboard with real-time provisional results. Submissions will be scored as soon as possible during the contest, the results posted. Contestants will be aware of their scores, but not others', may resubmit to improve their scores. Starting from 2012, IOI has been using the Contest Management System for developing and monitoring the contest; the scores from the two competition days and all problems are summed up separately for each contestant. At the awarding ceremony, contestants are awarded medals depending on their relative total score; the top 50% of the contestants are awarded medals, such that the relative number of gold: silver: bronze: no medal is 1:2:3:6. Prior to IOI 2010, students who did not receive medals did not have their scores published, making it impossible for a country to be ranked by adding together scores of its competitors unless each wins a medal. From IOI 2010, although the scores of students who did not receive medals are still not available in the official results, they are known from the live web scoreboard.
In IOI 2012 the top 3 nations ranked by aggregate score were subsequently awarded during the closing ceremony. Analysis of female performance shows 77.9 % of women obtain no medal, while 49.2 % of men obtain no medal. "The average female participation was 4.4% in 1989–1994 and 2.2% in 1996–2014." It suggests women participate much more on the national level, claiming sometimes a double-digit percentage of women participate on the first stage. President of the IOI, Richard Forster, says the competition has difficulty attracting women and that in spite of trying to solve it, "none of us have hit on quite what the problem is, let alone the solution."In IOI 2017 held in Iran, due to not being able to participate in Iran, the Israeli students participated in an offsite competition organized by IOI in Russia.:11 Due to visa issues, the full USA team was unable to attend, although one contestant Zhezheng Luo was able to attend by traveling with the Chinese team and winning gold medal and 3rd place in standings.
The following is a list of the top performers in the history of the IOI. The P sign indicates a rare achievement in IOI history; the U sign indicates an unofficial participation, where a contestant participated in a host's second team. First and third places among gold medalists are indicated where appropriate; this list includes only those countries where the national selection contest allows the same participant to go multiple times to the IOI. Most participating countries use feeder competitions to select their team. A number of these are listed below: International Science Olympiad ACM International Collegiate Programming Contest Central European Olympiad in Informatics Online judge International Mathematical Olympiad International Olympiad in Informatics community Facebook Group for the International Olympiad in Informatics IOI International Committee Website IOI Statistics IOI Secretariat Website
The EURion constellation is a pattern of symbols incorporated into a number of banknote designs worldwide since about 1996. It is added to help imaging software detect the presence of a banknote in a digital image; such software can block the user from reproducing banknotes to prevent counterfeiting using colour photocopiers. According to research from 2004, the EURion constellation is used for colour photocopiers but not used in computer software, it has been reported that Adobe Photoshop will not allow editing of an image of a banknote, but this is believed to be due to a different, unknown digital watermark rather than the EURion constellation. The name "EURion constellation" was coined by security researcher Markus Kuhn, who uncovered the pattern on the 10 Euro banknote in early 2002 while experimenting with a Xerox colour photocopier that refused to reproduce banknotes; the word is a portmanteau of EUR, the euro's ISO 4217 designation, Orion, a constellation of similar shape. The EURion constellation first described by Kuhn consists of a pattern of five small yellow, green or orange circles, repeated across areas of the banknote at different orientations.
The mere presence of five of these circles on a page is sufficient for some colour photocopiers to refuse processing. Some banks integrate the constellation with the remaining design of the note. On 50 DM German banknotes, the EURion circles formed the innermost circles in a background pattern of fine concentric circles. On the front of former Bank of England Elgar £20 notes, they appear as green heads of musical notes. On some U. S. bills, they appear as the digit zero in yellow numbers matching the value of the note. On Japanese yen, these circles sometimes appear as flowers. Technical details regarding the EURion constellation are kept secret by its users. A 1995 patent application suggests that the pattern and detection algorithm were designed at Omron Corporation, a Japanese electronics company, it is not clear whether the feature has any official name. The term "Omron anti-photocopying feature" appeared in an August 2005 press release by the Reserve Bank of India. In 2007 the term "Omron rings" was used in an award announcement by a banknote collectors society.
The following table lists the banknotes. Countries where all recent banknotes use the constellation are in bold. Since 2003, image editors such as Adobe Photoshop CS or Paint Shop Pro 8 refuse to print banknotes. According to Wired.com, the banknote detection code in these applications, called the Counterfeit Deterrence System, was designed by the Central Bank Counterfeit Deterrence Group and supplied to companies such as Adobe as a binary module. Experiments by Steven J. Murdoch and others showed that this banknote detection code does not rely on the EURion pattern, it instead detects a digital watermark embedded in the images, developed by Digimarc. Printer steganography, used by some colour laser printers to add hidden encoded information to printouts Coded anti-piracy, an anti–copyright-infringement technology which marks each film print of a motion picture with a distinguishing patterns of dots, used as a forensic identifier to identify the source of illegal copies "Photoshop and CDS". Adobe Systems Incorporated.
The rules for currency image use- website of the Central Bank Counterfeit Deterrence Group Nieves, J.. & Bringas, P.'Recognizing Banknote Patterns for Protecting Economic TransactionsDatabase and Expert Systems Applications, 2010 Workshop on', IEEE, 247--249. Data Genetics, Anti Counterfeit Measures
A digital watermark is a kind of marker covertly embedded in a noise-tolerant signal such as audio, video or image data. It is used to identify ownership of the copyright of such signal. "Watermarking" is the process of hiding digital information in a carrier signal. Digital watermarks may be used to verify the authenticity or integrity of the carrier signal or to show the identity of its owners, it is prominently used for banknote authentication. Like traditional physical watermarks, digital watermarks are only perceptible under certain conditions, i.e. after using some algorithm. If a digital watermark distorts the carrier signal in a way that it becomes perceivable, it may be considered less effective depending on its purpose. Traditional watermarks may be applied to visible media, whereas in digital watermarking, the signal may be audio, video, texts or 3D models. A signal may carry several different watermarks at the same time. Unlike metadata, added to the carrier signal, a digital watermark does not change the size of the carrier signal.
The needed properties of a digital watermark depend on the use case. For marking media files with copyright information, a digital watermark has to be rather robust against modifications that can be applied to the carrier signal. Instead, if integrity has to be ensured, a fragile watermark would be applied. Both steganography and digital watermarking employ steganographic techniques to embed data covertly in noisy signals. While steganography aims for imperceptibility to human senses, digital watermarking tries to control the robustness as top priority. Since a digital copy of data is the same as the original, digital watermarking is a passive protection tool, it just does not degrade it or control access to the data. One application of digital watermarking is source tracking. A watermark is embedded into a digital signal at each point of distribution. If a copy of the work is found then the watermark may be retrieved from the copy and the source of the distribution is known; this technique has been used to detect the source of illegally copied movies.
The term "Digital Watermark" was coined by Andrew Tirkel and Charles Osborne in December 1992. The first successful embedding and extraction of a steganographic spread spectrum watermark was demonstrated in 1993 by Andrew Tirkel, Charles Osborne and Gerard Rankin. Watermarks are identification marks produced during the paper making process; the first watermarks appeared in Italy during the 13th century, but their use spread across Europe. They were used as a means to identify the paper maker or the trade guild that manufactured the paper; the marks were created by a wire sewn onto the paper mold. Watermarks continue to prevent forgery. Digital watermarking may be used for a wide range of applications, such as: Copyright protection Source tracking Broadcast monitoring Video authentication Software crippling on screencasting and video editing software programs, to encourage users to purchase the full version to remove it. ID card security Fraud and Tamper detection. Content management on social networks The information to be embedded in a signal is called a digital watermark, although in some contexts the phrase digital watermark means the difference between the watermarked signal and the cover signal.
The signal where the watermark is to be embedded is called the host signal. A watermarking system is divided into three distinct steps, embedding and detection. In embedding, an algorithm accepts the host and the data to be embedded, produces a watermarked signal; the watermarked digital signal is transmitted or stored transmitted to another person. If this person makes a modification, this is called an attack. While the modification may not be malicious, the term attack arises from copyright protection application, where third parties may attempt to remove the digital watermark through modification. There are many possible modifications, for example, lossy compression of the data, cropping an image or video, or intentionally adding noise. Detection is an algorithm, applied to the attacked signal to attempt to extract the watermark from it. If the signal was unmodified during transmission the watermark still is present and it may be extracted. In robust digital watermarking applications, the extraction algorithm should be able to produce the watermark even if the modifications were strong.
In fragile digital watermarking, the extraction algorithm should fail if any change is made to the signal. A digital watermark is called robust with respect to transformations if the embedded information may be detected reliably from the marked signal if degraded by any number of transformations. Typical image degradations are JPEG compression, cropping, additive noise, quantization. For video content, temporal modifications and MPEG compression are added to this list. A digital watermark is called imperceptible if the watermarked content is perceptually equivalent to the original, unwatermarked content. In general, it is easy to create either robust watermarks—or—imperceptible watermarks, but the creation of both robust—and—imperceptible watermarks has proven to be quite challenging. Robust imperceptible watermarks have been proposed as a tool for the protection of digital content, for example as an embedded no-copy-allowed flag
X Window System
The X Window System is a windowing system for bitmap displays, common on Unix-like operating systems. X provides the basic framework for a GUI environment: drawing and moving windows on the display device and interacting with a mouse and keyboard. X does not mandate the user interface – this is handled by individual programs; as such, the visual styling of X-based environments varies greatly. X originated at the Massachusetts Institute of Technology in 1984; the X protocol has been version 11 since September 1987. The X. Org Foundation leads the X project, with the current reference implementation, X. Org Server, available as free and open source software under the MIT License and similar permissive licenses. X is an architecture-independent system for remote graphical user interfaces and input device capabilities; each person using a networked terminal has the ability to interact with the display with any type of user input device. In its standard distribution it is a complete, albeit simple and interface solution which delivers a standard toolkit and protocol stack for building graphical user interfaces on most Unix-like operating systems and OpenVMS, has been ported to many other contemporary general purpose operating systems.
X provides the basic framework, or primitives, for building such GUI environments: drawing and moving windows on the display and interacting with a mouse, keyboard or touchscreen. X does not mandate the user interface. Programs may use X's graphical abilities with no user interface; as such, the visual styling of X-based environments varies greatly. Unlike most earlier display protocols, X was designed to be used over network connections rather than on an integral or attached display device. X features network transparency, which means an X program running on a computer somewhere on a network can display its user interface on an X server running on some other computer on the network; the X server is the provider of graphics resources and keyboard/mouse events to X clients, meaning that the X server is running on the computer in front of a human user, while the X client applications run anywhere on the network and communicate with the user's computer to request the rendering of graphics content and receive events from input devices including keyboards and mice.
The fact that the term "server" is applied to the software in front of the user is surprising to users accustomed to their programs being clients to services on remote computers. Here, rather than a remote database being the resource for a local app, the user's graphic display and input devices become resources made available by the local X server to both local and remotely hosted X client programs who need to share the user's graphics and input devices to communicate with the user. X's network protocol is based on X command primitives; this approach allows both 2D and 3D operations by an X client application which might be running on a different computer to still be accelerated on the X server's display. For example, in classic OpenGL, display lists containing large numbers of objects could be constructed and stored in the X server by a remote X client program, each rendered by sending a single glCallList across the network. X provides no native support for audio. X uses a client–server model: an X server communicates with various client programs.
The server sends back user input. The server may function as: an application displaying to a window of another display system a system program controlling the video output of a PC a dedicated piece of hardwareThis client–server terminology – the user's terminal being the server and the applications being the clients – confuses new X users, because the terms appear reversed, but X takes the perspective of the application, rather than that of the end-user: X provides display and I/O services to applications, so it is a server. The communication protocol between server and client operates network-transparently: the client and server may run on the same machine or on different ones with different architectures and operating systems. A client and server can communicate securely over the Internet by tunneling the connection over an encrypted network session. An X client itself may emulate an X server by providing display services to other clients; this is known as "X nesting". Open-source clients such as Xnest and Xephyr support such X nesting.
To use an X client application on a remote machine, the user may do the following: on the local machine, open a terminal window use ssh with the X forwarding argument to connect to the remote machine request local display/input service The remote X client application will make a connection to the user's local X server, providing display and input to the user. Alternatively, the local machine may run a small program that connects to the remote machine and starts the client application. Practical examples of remote clients include: administering a remote machine graphically using a client application to join with large numbers of other terminal users in collaborative workgroups running a computationally intensive simulation on a remote machine and displaying the results on
University of Cambridge
The University of Cambridge is a collegiate public research university in Cambridge, United Kingdom. Founded in 1209 and granted a Royal Charter by King Henry III in 1231, Cambridge is the second-oldest university in the English-speaking world and the world's fourth-oldest surviving university; the university grew out of an association of scholars who left the University of Oxford after a dispute with the townspeople. The two'ancient universities' share many common features and are referred to jointly as'Oxbridge'; the history and influence of the University of Cambridge has made it one of the most prestigious universities in the world. Cambridge is formed from a variety of institutions which include 31 constituent Colleges and over 100 academic departments organised into six schools. Cambridge University Press, a department of the university, is the world's oldest publishing house and the second-largest university press in the world; the university operates eight cultural and scientific museums, including the Fitzwilliam Museum, as well as a botanic garden.
Cambridge's libraries hold a total of around 15 million books, eight million of which are in Cambridge University Library, a legal deposit library. In the fiscal year ending 31 July 2018, the university had a total income of £1.965 billion, of which £515.5 million was from research grants and contracts. In the financial year ending 2017, the central university and colleges had combined net assets of around £11.8 billion, the largest of any university in the country. However, the true extent of Cambridge's wealth is much higher as many colleges hold their historic main sites, which date as far back as the 13th century, at depreceated valuations. Furthermore, many of the wealthiest colleges do not account for “heritage assets” such as works of art, libraries or artefacts, whose value many college accounts describe as “immaterial”; the university is linked with the development of the high-tech business cluster known as'Silicon Fen'. It is a member of numerous associations and forms part of the'golden triangle' of English universities and Cambridge University Health Partners, an academic health science centre.
As of 2018, Cambridge is the top-ranked university in the United Kingdom according to all major league tables. As of September 2017, Cambridge is ranked the world's second best university by the Times Higher Education World University Rankings, is ranked 3rd worldwide by Academic Ranking of World Universities, 6th by QS, 7th by US News. According to the Times Higher Education ranking, no other institution in the world ranks in the top 10 for as many subjects; the university has educated many notable alumni, including eminent mathematicians, politicians, philosophers, writers and foreign Heads of State. As of March 2019, 118 Nobel Laureates, 11 Fields Medalists, 7 Turing Award winners and 15 British Prime Ministers have been affiliated with Cambridge as students, faculty or research staff. By the late 12th century, the Cambridge area had a scholarly and ecclesiastical reputation, due to monks from the nearby bishopric church of Ely. However, it was an incident at Oxford, most to have led to the establishment of the university: two Oxford scholars were hanged by the town authorities for the death of a woman, without consulting the ecclesiastical authorities, who would take precedence in such a case, but were at that time in conflict with King John.
The University of Oxford went into suspension in protest, most scholars moved to cities such as Paris and Cambridge. After the University of Oxford reformed several years enough scholars remained in Cambridge to form the nucleus of the new university. In order to claim precedence, it is common for Cambridge to trace its founding to the 1231 charter from King Henry III granting it the right to discipline its own members and an exemption from some taxes. A bull in 1233 from Pope Gregory IX gave graduates from Cambridge the right to teach "everywhere in Christendom". After Cambridge was described as a studium generale in a letter from Pope Nicholas IV in 1290, confirmed as such in a bull by Pope John XXII in 1318, it became common for researchers from other European medieval universities to visit Cambridge to study or to give lecture courses; the colleges at the University of Cambridge were an incidental feature of the system. No college is as old as the university itself; the colleges were endowed fellowships of scholars.
There were institutions without endowments, called hostels. The hostels were absorbed by the colleges over the centuries, but they have left some traces, such as the name of Garret Hostel Lane. Hugh Balsham, Bishop of Ely, founded Peterhouse, Cambridge's first college, in 1284. Many colleges were founded during the 14th and 15th centuries, but colleges continued to be established until modern times, although there was a gap of 204 years between the founding of Sidney Sussex in 1596 and that of Downing in 1800; the most established college is Robinson, built in the late 1970s. However, Homerton College only achieved full university college status in March 2010, making it the newest full college. In medieval times, many colleges were founded so that their members would pray for the souls of the founders, were associated with chapels or abbeys; the colleges' focus changed in 1536 with the Dissolution of the Monasteries. King Henry VIII ordered the university to disband its Faculty of Canon Law and to stop teaching "scholastic philosophy".
In response, colleges changed
VideoCrypt is a cryptographic, smartcard-based conditional access television encryption system that scrambles analogue pay-TV signals. It was introduced in 1989 by News Datacom and was used by Sky TV and subsequently by several other broadcasters on SES' Astra satellites at 19.2° east. Three variants of the VideoCrypt system were deployed in Europe: VideoCrypt I for the UK and Irish market and VideoCrypt II for continental Europe; the third variant, VideoCrypt-S was used on a short-lived BBC Select service. The VideoCrypt-S system differed from the typical VideoCrypt implementation as it used line shuffle scrambling. Sky NZ and Sky Fiji may use different versions of the VideoCrypt standard based on VideoCrypt-S. Sky NZ used NICAM stereo for many years until abandoning it when the Sky DTH technology started replacing Sky UHF; the system scrambles the picture using a technique known as Line Cut-and-Rotate. Each line that made up each picture is cut at one of 256 possible "cut points", the two halves of each line are swapped around for transmission.
The series of cutpoints is determined by a pseudo-random sequence. Channels were decoded using a pseudorandom number generator sequence stored on a smart card. To decode a channel the decoder would read the smart card to check if the card is authorised for the specific channel. If not, a message would appear on screen. Otherwise the decoder seeds the card's PRNG with a seed transmitted with the video signal to generate the correct sequence of cut points; the system included a cryptographic element called the Fiat Shamir Zero Knowledge Test. This element was a routine in the smartcard that would prove to the decoder that the card was indeed a genuine card; the basic model was that the decoder would present the card with a packet of data which the card would process and return the result to the decoder proving that it was a genuine card without disclosing any critical information. If the decoder received the wrong result from the card, it was supposed to stop decoding the video; however a technologically insecure implementation of this otherwise strong cryptographic element made it redundant.
The VideoCrypt-S variant, used by the BBC Select service, was based on line shuffle scrambling. This form of video scrambling changes the order in which lines are transmitted thus line 20 may be transmitted as line 32; the VideoCrypt-S variant used six blocks of forty seven lines per field. It had three scrambling formats: full shuffle; the VideoCrypt system was far from secure and a number of hacks were employed. Although, the analog UHF option is still available, the introduction of Sky Digital has ameliorated these issues as the VideoGuard system employed by SkyDigital has not been defeated, as of 2009. Hackers discovered methods of preventing Sky from deactivating their cards; the simplest of these attacks relied on the fact that Sky was using EPROM technology for its smartcards at the time. Thus by modifying the decoder to limit the write voltage to the card, it was possible to stop cards being turned off over the air. Another, known as the KENtucky Fried Chip attack relied on replacing the microcontroller that controlled the smartcard to decoder interface.
This attack relied on blocking packets with the smartcard's identification number. The voltage based attack failed. Commercial pirates reverse engineered the Sky smartcard, removed the access control routines and created working pirate smartcards using different microcontroller types from that used by Sky. Hackers discovered ways of switching on "dead" cards using a computer and smartcard interface by sending a properly formatted and addressed activation packet to the card. Variations on this attack allowed existing subscriber cards to be upgraded to more expensive subscription packages; this attack was known as the "Phoenix Hack" after the mythical bird that could bring itself back to life. Other successful hacks involved sampling the datastream between the card and the decoder, for example you could record a movie and store the decoder information so that people could use it to decode the same movie that they recorded earlier with a decoder and "dummy" card; the attack was known as the Delayed Data Transfer hack and it worked because the conditional access data, decoder addressing and encrypted keys, were on the video lines that are recorded by normal VCRs and the data rate, unlike that of Teletext, was slow enough to allow the data to be recorded with the encrypted video.
The most successful hack on the VideoCrypt system is the "McCormac Hack" devised by John McCormac. This attack involved broadcasting the decryption keys from the decoder-card data live so that other decoders could use it to watch the encrypted channels sharing a card with several decoders. Card sharing is an implementation of the McCormac Hack; as desktop computing power increased, such a simple system was always inherently vulnerable to brute force'image-processing' attacks. Without any information at all about the cutpoint sequence, adjacent lines in a picture can be'correlated' to find the best match, the picture reconstructed; the Brute force method is an interesting proof-of-concept. Markus Kuhn's Antisky.c program from 1994 is an early example of such an
West Germany the Federal Republic of Germany, referred to by historians as the Bonn Republic, was a country in Central Europe that existed from 1949 to 1990, when the western portion of Germany was part of the Western bloc during the Cold War. It was created during the Allied occupation of Germany in 1949 after World War II, established from eleven states formed in the three Allied zones of occupation held by the United States, the United Kingdom and France, its capital was the city of Bonn. At the onset of the Cold War, Europe was divided among the Eastern blocs. Germany was de facto divided into two countries and two special territories, the Saarland and divided Berlin; the Federal Republic of Germany claimed an exclusive mandate for all of Germany, considering itself to be the democratically reorganised continuation of the 1871–1945 German Empire. It took the line. Though the GDR did hold regular elections, these were not fair. From the West German perspective, the GDR was therefore illegitimate.
Three southwestern states of West Germany merged to form Baden-Württemberg in 1952, the Saarland joined the Federal Republic of Germany in 1957. In addition to the resulting ten states, West Berlin was considered an unofficial de facto 11th state. While not part of the Federal Republic of Germany, as Berlin was under the control of the Allied Control Council, West Berlin politically-aligned itself with West Germany and was represented in its federal institutions; the foundation for the influential position held by Germany today was laid during the Wirtschaftswunder of the 1950s when West Germany rose from the enormous destruction wrought by World War II to become the world's third-largest economy. The first chancellor Konrad Adenauer, who remained in office until 1963, had worked for a full alignment with NATO rather than neutrality, he not only secured a membership in NATO but was a proponent of agreements that developed into the present-day European Union. When the G6 was established in 1975, there was no question whether the Federal Republic of Germany would be a member as well.
Following the collapse of communism in Central and Eastern Europe in 1989, symbolised by the opening of the Berlin Wall, there was a rapid move towards German reunification. East Germany voted to dissolve itself and accede to the Federal Republic in 1990, its five post-war states were reconstituted along with the reunited Berlin, which ended its special status and formed an additional Land. They formally joined the Federal Republic on 3 October 1990, raising the number of states from 10 to 16, ending the division of Germany; the reunion did not result in a brand-new country. The expanded Federal Republic retained West Germany's political culture and continued its existing memberships in international organisations, as well as its Western foreign policy alignment and affiliation to Western alliances like UN, NATO, OECD and the European Union; the official name of West Germany, adopted in 1949 and unchanged since is Bundesrepublik Deutschland. In East Germany, the terms Westdeutschland or westdeutsche Bundesrepublik were preferred during the 1950s and 1960s.
This changed once under its 1968 constitution, when the idea of a single German nation was abandoned by East Germany, as a result West Germans and West Berliners were considered foreigners. In the early 1970s, starting in the East German Neues Deutschland, the initialism "BRD" for the "Federal Republic of Germany" began to prevail in East German usage. In 1973, official East German sources adopted it as a standard expression and other Eastern Bloc nations soon followed suit. In reaction to this move, in 1965 the West German Federal Minister of All-German Affairs Erich Mende issued the Directives for the appellation of Germany, recommending avoiding the initialism. On 31 May 1974, the heads of West German federal and state governments recommended always using the full name in official publications. From on West German sources avoided the abbreviated form, with the exception of left-leaning organizations which embraced it. In November 1979 the federal government informed the Bundestag that the West German public broadcasters ARD and ZDF had agreed to refuse to use the initialism.
The ISO 3166-1 alpha-2 country code of West Germany was "DE", which has remained the country code of Germany after reunification. ISO 3166-1 alpha-2 are the most used country codes, the "DE" code is notably used as country identifier extending the postal code and as the Internet's country code top-level domain.de. Accordingly the less used ISO 3166-1 alpha-3 country code of West Germany was "DEU", which has remained the country code of reunified Germany; the now deleted codes for East Germany, on the other hand, was "DD" in ISO 3166-1 alpha-2 and "DDR" in ISO 3166-1 alpha-3. The colloquial term "West Germany" or its equivalent was used in many languages. "Westdeutschland" was a widespread colloquial form used in German-speaking countries without political overtones. On 4–11 February 1945 leaders from the United States, the United Kingdom and the Soviet Union held the Yalta Conference where future arrangements as regards post-war Europe and strategy against Japan in the Pacific were negotiated.
The conference agreed that post-war Germany would be divided into four occupation zones: a French Zone in the far west.