Memorials to mark the centenary of the sinking of the Titanic have taken place all over the world - but some people have taken to Twitter to admit that they didn't realise that the Titanic was a real ship.
A number of young people, who are only familiar with the Titanic in the context of the 1997 film starring Kate Winslet and Leonardo DiCaprio, were shocked to discover that the movie was actually based on a true story.
The Daily Mail reports that a screenshot of tweets from people who had just realised that the disaster really happened was first circulated on the social news site Reddit.
One tweeter wrote: "I never knew Titanic actually happened".
Another said: "Didn't know the Titanic actually happened. I thought it was just a film!"
Another user wrote: "Is it bad that I didn't know the Titanic was real? Always thought it was just a film."
Other tweeters were horrified to discover that some people assumed that the sinking of the Titanic was entirely fictional.
One commenter said: "The ignorance is astounding".
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