whats the difference between $ wget kernel.ubuntu.com/~kernel-ppa/mainline/v4.2-rc1-unstable/linux-headers-4.2.0-040200rc1_4.2.0-040200rc1.201507051635_all.deb and $ wget http://kernel.ubuntu.com/~kernel-ppa/mainline/daily/current/linux-headers-4.2.0-999_4.2.0-999.201507112205_all.deb i would like to know no just if one is higher than the other but i would like to know also if they are both upgradeable, once again bear with my poor grammar, thanks