One of the most important variable you hard is it's longevity. Though, many hard drives may stay alive as long as ten years many low quality hard drive wont' even make it for a year. Many professionals are specialized in Hard drive recovery, such work if usually very expensive, it all depends your hard drive current physical state.
There is one thing that most hard drive manufacturers will not tell you - most hard drives will fail although they are subject to normal conditions and use. The hard drive failure may take about ten years to happen, but in some instances, it can be less than a year. Well, whatever the case may be, it is very important to note and understand that when your hard drive fails, the professional hard drive data recovery is available but not 100% safe of recovery.
You can have the most expensive and well made hard drive, failure will always be one of the problems, you just cannot be protected against failure, as we always say "nothing is perfect"!
That's why the best weapon against failure is preventive backup, you have many different ways of backing up your files, from parallel hd backups with a RAID card to a USB or firewire external backup.
Best way to protect your data:
One of the best way to protect your data is to have multiple backup locations like your home HD, work HD and 1 or 2 usb sticks, try to use good softwares like Acronis in order to have perfect backups in place.
Acronis is excellent for backing up large and individual folders, it is quick,easy to use and a most have if you are looking for a styrong backup solution, the only bad point with such software is the price tag which might be a little too high for some.
Back up your user names and passwords:
The best way to protect your online and offline data is to use a software which keeps all your user names and passwords in one place, a excellent freeware which does exactly that is called Keepass and Keepass PRO, I highly recommend to download such cool freeware.
Now you might think, well, if I put all my passwords into one software on a USB stick and by mistake forget my stick in a cinema or restaurant, the thief will have access to everything!
Here is the trick, when you use this little freeware, it will ask you to create a password and will then encrypt all your data with a highly protective 256 Bit algorithm. If someone finds your password, he will first need to know your first password which will be in your head! If someone tries to decipher your data, please tell him/her that they will need decades in order to crack your 256 bit software.
Now you have access to some of the best software for your data security, if you run an offline or online business with a lot of accounts from different other firms, security is number 1! Do not hesitate to invest a little or time or money to protect your data and business.