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That means a possibly serious error has occurred. It may be, unfortunately, that your hard disk has become corrupted, or has 'crashed'.
But are you sure the hard disk setup in the BIOS is in good shape? if such settings were changed, spontaneously or otherwise, then the hard disk might become un-usable and thus seem to have no operating system installed on it.
How new is it, please?
And going into the Setup BIOS should show you the hard disk settings, and/or IDE and/or SATA settings, and setting them straight should be all that is needed, in some cases.
I don't know your laptop model, so I cannot provide data as to that.
Look in the Setup, find out first whether it has a IDE or EIDE section, or an SATA section.
(Those are systems of hard disk interface.)
Let me know what you find, please. And I will advise you further.