gcc && libstdc++

[Carlos Pita]

Hi!

    I have some newbie questions about using gcc with libstdc++. First, I
would like to know which sources of libstdc++ should I use: the ones in the
latest libstdc++ snapshot or the ones which comes with the latest gcc
snapshot? Then, should I expect new independent snapshots (I mean, not
provided with gcc distribution) of libstdc++ for the future? Third, why are
any language runtime libraries distributed with gcc: is this only a matter
of distribution or have they some source code dependencies on the specific
gcc version?
    Not related to the above questions: where can I find info about gcc
architecture, front and back ends, etc.?

    Well,  I hope any of you have the time to answer these basic questions.
    Thank you,
        Carlos