You've already receive your answers in other replies which are quite good. I would like to add a bit of explanation of what the deal is. You cannot do anything on a computer without a running system. I know this is trivial but many people don't think like that because there are used to it being taken care of for them.
Whether you want to install MAC OS X, Linux, WIndows ???, on a blank system (only disk does not have an OS on it), you need an attachable device from whihc you boot the install OS. With Linux and Windows, your install disk is a bootable device (whether CD, DVD, USB drive, or jump drive). When you instruct the computer to boot from it (the procedure varies with hardware. Sometimes you need to change the BIOS settings to have it look for removable bootable media. MAC OS X Snow leopard came that way as well. You put the install media in the drive and start the computer. Follow the instructions on the screen. Mac OS X used to be that way and Linux and Windows still are for now.
When Apple released Lion, they changed their world. They did not distribute by DVDs any more. WHen they installed Lion, they install the OS partition and a recovery partition. So you could fix it if the OS partition got hosed. Not well advertised but understood by many, it was possible if you bought your OS upgrade at the Mac App Store, from any Mac you could run on, you could log into the MAS and download the installer for that OS. Some have written utiities such as Lion Disk Maker that can run on some MAC system of recent vintage and install the downloaded Install image to a USB drive whihc you can boot and install on a clean system. This is quite useful if you had a disk hardware failure and need to replace the hard drive with a blank one.
Since the OS X on the boot image must work with the system you are using, you need to download the boot image from a version that has your computer hwardware in mind. This means if you replace the computer as well as the HD, you need a downloaded install image created after the new hardware was released. I ran into that issue and got help from the Lion Disk Maker developer.
Having install images that will run on any compatible hardware out there can be an issue and for that reason, OS manufacturers from time to time obsolete certain hardware. That was apparently the issue with the current question.
People have installed OS X on vanilla Intel computer systems. But Apple does not support that and does not like it as besides the loss of hardware sales, it makes the support issues far more difficult to deal with. That is one place hwere Microsoft has a very hard world to work with. For years I would swear at Hewlett Packard PCs since their engineers always wanted to do it better. What they did was not always compatible and I had a lot of hardware compibility issues. They had trouble learning that Standard was better then Better. By not supporting clones, Apple avoided tht problem. They are also a more expensive hardware solution.
I can afford Apple Hardware and i find that makes life very easy. I once bought what seemed like a pretty good HP tower system and spent years trying to keep Linux working. Everything was non-standard. If I wanted to run Windows, they had an answer for that but Linux, (we do not support Linux on that model - official HP reply).
I've worked on low level software / firmware on Intel PCs. It is not as easy as it might seem. You can do everyhint using BIOS calls but then it is slow as molasass.
Bruce