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Google Translate is a free tool that enables you to translate sentences, documents and

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even whole websites instantly.

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But how exactly does it work? While it may seem like we have a room full of bilingual

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elves working for us, in fact all of our translations come from computers. These computers use a

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process called “statistical machine translation” -- which is just a fancy way to say that our computers

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generate translations based on patterns found in large amounts of text.

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But let’s take a step back. If you want to teach someone a new language you might

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start by teaching them vocabulary words and grammatical rules that explain how to construct

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sentences. A computer can learn a foreign language the same way - by referring to vocabulary

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and a set of rules.

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But languages are complicated and, as any language learner can tell you, there are exceptions

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to almost any rule. When you try to capture all of these exceptions, and exceptions to

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the exceptions, in a computer program, the translation quality begins to break down.

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Google Translate takes a different approach. Instead of trying to teach our computers all

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the rules of a language, we let our computers discover the rules for themselves. They do

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this by analyzing millions and millions of documents that have already been translated

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by human translators. These translated texts come from books, organizations like the UN

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and websites from all around the world.

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Our computers scan these texts looking for statistically significant patterns--that is

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to say, patterns between the translation and the original text that are unlikely to occur

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by chance. Once the computer finds a pattern, it can use this pattern to translate similar

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texts in the future. When you repeat this process billions of times you end up with

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billions of patterns and one very smart computer program.

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For some languages however we have fewer translated documents available and therefore fewer patterns

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that our software has detected. This is why our translation quality will vary by language

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and language pair. We know our translations aren’t always perfect but by constantly

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providing new translated texts we can make our computers smarter and our translations

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better.

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So next time you translate a sentence or webpage with Google Translate, think about those millions

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of documents and billions of patterns that ultimately led to your translation - and all

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of it happening in the blink of an eye.

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Pretty cool, isn’t it?

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Give it a try at translate.google.com.