Formatting a laptop is a process in which you erase the data on the hard drive of the laptop. This process is often done to prepare the laptop for other uses, such as hosting a new operating system. If you're formatting a laptop, you don't have to worry much about passwords, but there's some useful information you should know that will make the formatting process easier.
Operating System Passwords
If you're performing a format on a computer, the operating system passwords are the least of your worries. Because the operating system is simply data stored on a computer's hard drive, you can format the hard drive without ever booting the operating system. In fact, this is the best way to format the computer, since you'll be able to erase the data on the hard drive, including the operating system files. If you're installing a new operating system on your laptop, you can perform a quick format during the installation to quickly wipe away the old operating system--and any associated passwords.
BIOS Password Formatting Troubles
If you want to format a laptop that has a BIOS password enabled, you might be troubled by the inability to bypass the BIOS password. Although you don't necessarily have to have access to the laptop's BIOS to format the computer, you may need to gain access to perform customization. If so, you can reset the BIOS password by removing the motherboard battery, referred to as a CMOS battery, or by changing special wires on the motherboard (see Resources). Once the password has been reset, you'll be able to access the BIOS to change settings and configure things like the boot sequence of the laptop.
Formatting with a Boot CD
Using a boot CD like Darik's Boot and Nuke or KillDisk, free software programs that perform a low-level format of the computer's hard drive, is a great way to totally erase all data on the hard drive. As long as you can boot from the CD, it doesn't matter what passwords are on the computer. Formatting the hard drive is an operation done outside of the operating system, so even if your computer has been encrypted, it can still be formatted and securely erased with a boot CD.