The hard disk is the hardest worker in your pc. The hard disk spins very very fast and spends all day reading and writing and copying and pasting and searching files that sometimes , it can get very hot. The heat generated can cause it to fail. The most common cause of failure is if you pick your laptop up with one hand. The hard disk is usually placed to the lower left of your laptop keyboard, and thats usually the place that laptop companies place thier hard disks. That sadly is the area that most of us, when the laptop is on, will pick it up. You will be squeezing the hard disk that is in your laptop. Pick your laptop up with 2 hands and save your laptop hard disk. This problem will not usually occur on a tablet computer this is the benefit of the new tablets out on the market. Tablet repairs are quite rare these days.
If your drive has failed you will need to try to get the data off of it. If you cant you will need to replace the hard disk and reload windows. For all hard disk errors call today for free advice.