NEW YORK (CNNMoney.com) -- In Turkey, it's a crime to defame the country's founder, Mustafa Kemal Ataturk or to ridicule "Turkishness." So Google restricts access to videos that the government of Turkey deems illegal on google.com.tr.
In Germany, France and Poland, it is illegal to publish pro-Nazi material or content that denies the Holocaust. To comply with those countries' laws, Google (GOOG, Fortune 500) does not display links to those sites on its search results pages on the company's German site google.de, French site google.fr or Polish site google.pl.
And in Thailand, denigrating the Thai monarch is against the law, so Google blocks YouTube videos in Thailand that ridicule King Bhumibol Adulyadej.
Google controls nearly two-thirds of the world's search results, making it the Internet gateway for most people. As a result of that clout, Google's censorship policies are closely watched.
That heady responsibility is also one of the reasons why Google may exit China, which has stringent censorship rules.
Google has a longstanding policy of censoring search results or hosted content, like videos, for people in nations where that material is illegal. But Google is in the process of deciding how to handle censorship in China, where that nation's policies are murky.
For example, Google may not agree with Germany's censorship laws, but that country has a government elected by the people, and it is transparent with its citizens about what it censors. On the other hand, China's government is not democratically elected, and its censorship laws are a state secret.
"When we first went into China, we were doing so with open eyes: We thought we could provide more access to information by being in China and censoring some information than not being there at all," said Scott Rubin, public policy spokesman for Google. "We always reserved the right to change our minds."
On Jan. 12, Google announced that it would no longer censor content on its Chinese search site after an investigation found that hackers had tried to access Gmail accounts of Chinese activists back in December.
Google has not taken any action yet as it continues to negotiate with the Chinese government. But ultimately, the company expects its decision to stop censoring will lead to shutting down google.cn. An announcement could come as early as Monday, according to news reports.
Some countries, like China, give Google and other search companies terms and topics that are considered illegal, and it is up to Google to determine whether a certain site breaks local law. Other countries make ad-hoc requests to take down certain links or content.
When a country asks Google to remove content or links, Google's lawyers examine the request to determine if it is, in fact, against that nation's laws. Often Google will negotiate with that country's authorities to narrow the scope of the requested restriction. And on occasion, Google doesn't comply, and countries restrict access.
In fact, Google sites have, at one time or another, been blocked in more than 25 different nations: China, Thailand, Turkey, Saudi Arabia, Iran, Cuba, North Korea, Pakistan, Morocco, Syria, Indonesia, Burma, Fiji, Ethiopia, the United Arab Emirates, Tunisia, Belarus, Uzbekistan, Bahrain, Vietnam, Turkmenistan, Bangladesh, India, Brazil and Spain.
Currently, Turkey doesn't allow Internet users within its borders to access YouTube, Google's online video site. The Turkish courts weren't satisfied with Google's decision to block illegal videos only within Turkish borders, because the videos are still available globally.
While Google users around the globe have access to the mostly unfiltered google.com and its partner sites, individual countries can still block access to those sites. Google said it is in talks with Turkish authorities and is hopeful YouTube will be restored for Turkish users soon.
One of Google's main goals is to be as transparent as possible. Any time Google censors something, it displays a message on its search results page explaining that the links have been removed. Google also provides a link to chillingeffects.com, a Web site run by Harvard's Berkman Center that records online content that has been censored.
It's not just foreign countries that Google censors. In the United States, Google frequently removes links or videos of content that the host site does not hold the copyright to.
Some censored "results" in America are ads. For example, results for "how to make a cherry bomb" and "where to buy heroin" return search results that give detailed information for both, because it is not illegal in the United States to instruct people how to build bombs or look up where to buy drugs. But Google does not display ads for either search query, because it is illegal to buy or sell cherry bombs or heroin.
The most tangible example of censorship at home is child pornography. While most U.S. censorship comes in response to a request from a copyright holder, Google says it is proactive about removing links to sites or videos that contain child pornography. Google has a policy of censoring those results in every nation, even those that do not have laws against child porn.
On the flip side, Google is sometimes criticized for not censoring other material in the United States. For many years, the top result after a search for "Jew" on google.com would return a link to jewwatch.com, a Web site that posts anti-Semitic articles. (The site is now the second result, following a Wikipedia article on the religion.)
Many organizations have pleaded with Google to remove the site from its search results, but Google has refused, citing its policy to only remove content that is illegal. Google now tops its search results page for the query "Jew" with a link to google.com/explanation in a sponsored link that states, "We're disturbed about these results as well." (See correction below)
Google's mission statement is "to organize the world's information and make it universally accessible and useful." Though it may not always be able to follow that mission to the letter, the search leader is at very least open and transparent about the kind of information that it restricts.
Correction: An earlier version of this story incorrectly stated that the Anti-Defamation League was one of the organizations that asked Google to remove the link to jewwatch.com. The ADL asked for an informative link that is displayed every time "Jew" is searched on Google.
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