Traits were added because you have magic_quotes_gpc=On in your php.ini . Please note that this function has been repaired and you must disable it in php.ini . It was a former security feature, but you should not rely on it. Instead, write code for yourself that evaluates all the inputs and uses prepared statements when passing the input to SQL queries, or uses escapeshellarg() if you pass input to shell scripts.
However, use stripslashes() to remove the slash:
echo stripslashes($_GET['user']);
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