..ah, the joys of starting a question with Why. Makes people read it cos they want to find out what is the question! Right. Why are the power cables, the power sockets, the hard disk sockets etc etc designed to have 80pins, or 4pins? Why must there be 5 or 6 different red and yellow cables running in to a card? Surely when the egg-heads (whom I am eternally grateful to), were developing PC's, did they decide to make the cables such a way? What happened to the traditional 3 pronged plug and a small black jack?
You mean the wires from the PSU? They're just coloured that way for positive/negative rail and ground.
yeah, it's just coloured for identification purposes. Cables are coloured black for ground, If I'm not mistaken yellow is +12v and red is +5v.
Guess my question wasn't too clear! I mean why are the connectors the way they are? Why have the Hard disks got to be connect with an 80pin cable, and not just 1? Why the power cables have 4 pins, and not just one?
Power you gotta have a ground, positive and a negative for DC. Then power has 12volt, and 5 volt and 3.3volt rails. Hard drive, well 80-pin just to transer data... 1pin hard drive cable wouldn't work just because it would have nothing for bandwidth even if it worked
Another thing would be to prevent people from plugging, say an external 25-pin SCSI cable into a parallel port (this is not a good thing from the pix I've seen). Second of all, having different interfaces for data connections helps figure out what you're looking for. There's also the requirements of the device, like a SCSI drive's setup to be different than an IDE drive in at least the electronics on the drive, in order to accomodate the standard.
In addition to foolproof installation, the number of pins translates into the number of lines for data to travel through. The number of lines can become irrelavent if the size or gauge of the line is increased. Also dependant on the media that is being used. As technology has improved, and the protocols advance we will see smaller cables (SATA) and faster throughput.