What are some password considerations when dealing with BIOS/CMOS?

System passwords allow you to prevent someone from booting your computer without the proper password.
However, since the password is stored in CMOS and CMOS retains its memory via battery, removal of the battery will wipe the system password (along with any other CMOS settings including date and time).
System or boot passwords offer a level of security, but don’t be fooled into a false sense of it. It will keep most people out of your system, but it can be bypassed.