Usually you see 3 different Classifications of parts; Retail, Bulk and OEM.
OEM usually means it has no manual and packed very minimally. No fancy packaging or anything like that.
For a processor OEM means you will get the processor and that is it. Bulk is almost the same thing for a processor. Bulk usually mean it came out of a carton or a box of parts that were all the same. Retail for a processor usually means that the processor may have a small pamplet explaining how to install or what the settings may be and that it probably comes with a heatsink and fan.
Hard drives are a little different. OEM is usually just the bard hard drive. It may be in an anti-static bag. Most hard drives that I have seen come in an antistatic bag. The OEM variety just come bare with no drivers or anything else. They have a sticker on the drive explaining the setting you need to know. Bulk may be just the same more or less. Retail for a hard drive usually means that it comes with a driver disk that may have the drive utilities on it or a special setup disk. It may also come with a cable and some mounting screws.
Most motherboards have enough cables for the hard drives and optical drives. Most computer cases come with the mounting hardware which contains suitable screws for a hard drive and the motherboard as well.
Some other devices like a video card will come with a driver disk or two even though they may be bulk or OEM.
This is why I like to shop at
www.newegg.com/
Normally at new egg they show you the books and drivers disks that come with a product and pictures of the product that are pretty thorough.
Bulk and OEM are basically the same thing. Often bulk parts come in a tray or a carton or a case. In the past I have seen a tray full of processors displayed in a glass case for sale. I purchased my last processor as retail and the CPU cooler worked quite well.