Traditional Culture Encyclopedia - Traditional culture - Why do all CD-ROM systems boot from a USB flash drive?

Why do all CD-ROM systems boot from a USB flash drive?

Security system protection settings for CDH.

1, boot into the boot press f2 to enter to the last item restart change osoptimizeddefaults to disabled.

2, into the startup press f9 then select uefi/legacyboot change to legacyonly can turn off the u-disk boot.