"Although Broadcom had very good in-house Linux drivers
for its wireless cards, which it sold to manufacturers of wireless
routers that ran on Linux, it refused to release the drivers to the
community, even in binary-only form, or to provide documentation
that would assist Linux users in writing their own drivers.
Consequently, ndiswrapper was for many years the only way to get
Broadcom cards running on Ubuntu and other
distributions."