You must have spent years by now working on your PC and created perhaps thousands of files such as images, documents, videos, databases and hundreds of other formats. Even when you upgrade your PC you take great care to transfer the older data from your own computer or hard disk to the new computer or hard disk. No matter how careful you are sooner or later everybody goes through that harrowing experience of losing data. You may accidentally delete your fires, the operating system may refuse to load, or the hard disk may go bad. Whatever is the reason, whenever it seems that you have lost your data you desperately want to recover it.
But the recovery cannot happen when the catastrophe has hit you. You need to be prepared for it or at least you should be having another PC or laptop or even another operating system running on the same machine in order to recover your PC data. So always keep a bootable CD/DVD at hand. These days you can also create bootable thumb drives. The point is, if you can not boot from your actual hard disk there must be some media using which you should be able to boot your PC.
Some of the best PC data recovery tools are discussed in this Lifehacker blog post.
