The world's major cities are melting pots, filled with people from different origins, different cultures, using different languages. The populations in these cities flux and change over time.

Now, a newly released interactive from Google News Lab aims to show how shifts in the languages different cities use to search can reflect changes in immigration and tourism.

"There are over 3 billion searches a day around the world and I was curious about whether those change over time," Simon Rogers of the News Lab explains in an e-mail, "and whether they reflect actual events in the world."

Does the information reflect real changes? It may well. For example, take a look at the gif above, which shows the top languages used to search Google in London (with the exception of English, which is number one by a margin). At first, the data shows Polish and French as being especially popular in the British capital, which makes sense: Polish immigrants are a large and visible minority in London, and by some measures the British capital is France's sixth-largest city.

What's more surprising is that according to Google, after 2007, the percentage of Spanish language searches in London jumped dramatically. By 2009 and 2010, roughly a fifth of all Google searches from London were in Spanish, a quite remarkable figure that may reflect the large number of Spanish immigrants who fled to Britain after the Spanish economy faltered.

The interactive also allows you to look at different language use in the nine cities studied (Berlin, Delhi, London, Madrid, New York, Paris, Sao Paulo, Shanghai and Toronto), which can produce some interesting results. For example, in a number of years for which Google has data, Delhi beats out London, New York and Toronto for the largest percentage of English-language searches.

Of course, the data can't show everything: Google doesn't have a huge part of the market in China due to censorship issues, for example, so the searches in Shanghai may not be representative. Even so, you can play around with the interactive yourself below:

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