If you ever had a laptop stolen or lost, I bet you wish you had full disk encryption on!
There are many variations of disk or drive encryption, but in a nutshell it is an encryption of the blocks of a hard drive where you must enter a password or pin before you can even boot your computer.
So the way it works is as follows;
Step one; Encrypt the drive utilizing whichever tool you chose. There are free ones, many that you can buy, and also if you have the Pro or higher version of Microsoft operating system there is a built-in encryption that you can used called BitLocker.
Step two; At the time when you activate the disk encryption, the process will ask you to create a password or a pin or store the key on a USB drive. This encryption key will be required each time you boot up the computer.
Step three; Once disk encryption has been configured, after you shut down the computer, the next time you start it, the operating system will not be able to load because the contents of the drive are completely scrambled by the encryption.
There will be a pre-boot logon screen where you will need to enter the encryption key password. Once you enter the password, the operating system can now load because it will then be able to see the contents of the drive.
– Gartner, a technology research firm
Disk encryption protects your data from prying eyes.
Disk encryption not only protects your lost or stolen laptop from someone getting into the operating system. If they remove the hard drive from the laptop and try to view the contents of the drive on another machine, it will be completely scrambled due to the encryption.

So the net result of the laptop is that the disk in it is literally a brick. The only option may be to either replace the hard drive with a new one, or wipe and reload the operating system on the current drive. They will be able to use the laptop moving forward if they do so, but they will not gain access to any of your data.
Data security and Disk Encryption must be part of any IT security plan, regardless if you are a one-person business or have many employees. It is not uncommon for a small business owner to have QuickBooks or similar accounting package on their laptop that they travel to work with. It is not uncommon, unfortunately, for people to keep their tax returns and other banking data in PDF files on their laptops.
So just like anything else in life, as the saying goes, “If you don’t plan, you plan to fail”
– Benjamin Franklin