For no apparent reason, with no warning whatsoever, my laptop hdd crashed while I was using it in class.

Although I have bought a new hdd and 'resurrected' my laptop, I have lost quite a lot of data (namely, photos and videos) that are stored in my hdd. So I sent my broken hdd to DataSavers for a free evaluation on data recovery. This is their quotation:

Dear Mr Guay,

Good day to you and how are you? Thank you for submitting your hard disk to
us. Rest assured that we will do our best to recover your data.

Our data recovery specialist had done an evaluation on your hard disk.

The head in the hard disk is electrically damaged. This in turn has caused
it to be misaligned, causing file read write access errors.

Slight scratches can also be found on the platter due to misaligned head
scratching its surface. These scratches have affected some of the sectors
where your data is residing. We will need to procure an identical model and
revision number hard disk to perform a head and platter swap to recover the
data. The platter then needs to be refurbished in a clean room environment
moving forward.

Data should be recoverable if there platter damage is not too severe. We
will only know the detailed results pending further work. Please find
attached the quotation for your job with a 5% home user discount.

Moral of this story: a simple backup may save you thousands of dollars.