[Ilugc] Ubuntu Free Software License - Clarification Needed

[Yogesh Girikumar]

Hi All,

Please see: http://www.markshuttleworth.com/archives/77#comment-34278

Can someone please enlighten me on what Mark means by "binary-blob drivers"?
I also don't understand how  making them proprietary makes the OS open
source. I know that FSF doesn't recognize Ubuntu as a FreeLibre Software
since it let's people download and use proprietary drivers. But what they
claim is that "All parts of Ubuntu will always be free, along with the
source code", right?? Or am I not seeing something here??

Thank You,
Yogesh.