DKMS (Dynamic Kernel Module Support) is a framework where device driver source can reside outside the kernel source tree so that it is very easy to rebuild modules as you upgrade kernels. This allows Linux vendors to provide driver drops without having to wait for new kernel releases (as a stopgap before the code can make it back into the kernel), while also taking out the guesswork for customers attempting to recompile modules for new kernels. For veteran Linux users it also provides some advantages since a separate framework for driver drops will remove kernel releases as a blocking mechanism for distributing code.
firmware-tools is an architecture that utilizes native Linux packaging formats (.rpm and .deb) and native Linux change management frameworks (yum, apt, etc) for delivering and installing system firmware. This architecture is OS distribution, hardware vendor, device, and change management system agnostic.
biosdevname in its simplest form takes a kernel device name as an argument, and returns the BIOS-given name it "should" be. This is necessary on systems where the BIOS name for a given device (e.g. the label on the chassis is "Gb1") doesn't map directly and obviously to the kernel name (e.g. eth0).