Your questions isn't too specific but I hope this helps
There are several ways to incorporate password protection. You can set the computer to require a boot up password in the computer BIOS. You have to enter the computer BIOS as soon as you turn it on; with a Dell press [F2], with HP press [Esc] and select system configuration. In the BIOS you can set the BIOS Administrator password - controls the ability to change BIOS settings, the computer boot password - when enabled it requires the user to enter the bootup password before the computer will boot, and set the hard drive access password - controls the users ability to access a hard drive.
The next level of password protection is at the operating system level - account access levels, privilege levels, and passwords. Dependent of operating system you can also set hard drive encryption
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Your questions isn't too specific but I hope this helps
There are several ways to incorporate password protection. You can set the computer to require a boot up password in the computer BIOS. You have to enter the computer BIOS as soon as you turn it on; with a Dell press [F2], with HP press [Esc] and select system configuration. In the BIOS you can set the BIOS Administrator password - controls the ability to change BIOS settings, the computer boot password - when enabled it requires the user to enter the bootup password before the computer will boot, and set the hard drive access password - controls the users ability to access a hard drive.
The next level of password protection is at the operating system level - account access levels, privilege levels, and passwords. Dependent of operating system you can also set hard drive encryption