Paths problem works '/file.xyz' doesn't work '../file.xyz' on the Web not in localhost?

Why does path like '/file.xyz' works on the web but do开发者_JS百科es not in localhost?

I'm using Xampp

In localhost I had to change it to '../file.xyz'

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Windows uses a backslash rather than a forward slash. Use realpath($path) to get the correct path for the system.

http://www.php.net/realpath