DVR A04 DVR A 06

please advice where i can learn about what is A04, A06 and the diffrances etc.
does A06 dvd burner support / compatible to A04 burner? does what A04 does and more?
who can i know what is any dvd burner – most of the manufacturers do not write any thing about it and when i aske
them , i get ” I believe the drive is comparable to the AO4 ……….” and give me the spec.
and the spec. doesnt say any thing about it.
the DVD i checked about is LG GSA-4040B
thank you very much