The CPU, or microprocessor in a computer is connected to the motherboard by a socket. There are many types of socket, one is called socket A. there are 462 pins in socket A which is also why it is called socket 462. this technology is used by AMD for the range of K7 processors.
The Hard drive of a computer is used to save files, music, movies and many more things. The standard internal HDD used to be connected by EIDE, but that has been replaced by Sata cable as it is quicker than EIDE. External harddrives may also be connected via the USB ports of a computer
The fans in a PC are used to withdraw hot air given off by components, and replace it with cool air. This will cool the components down and stop them from overheating. The Fans are connected to the PSU via a Molex cable like this one
Optical drives can read or store data on an optical disc like, DVDs, bluray discs or CD’s. it uses a laser to read data from, or write data onto a hard drive, this provides a convenient removable storage space for the user. They are connected to the hard drive with a SCSI connector.
Usb 2.0 is the universal connector used to connect external drives to the computer such as external HDD, ODD or other devices like iphone ETC. There will soon be a USB 3.0 which will be a lot faster than USB 2.0
A wireless adapter card can be connected to the motherboard of a pc to allow it to access the internet wirelessly. They can be connected via a USB 2.0 port, or a PCMCIA slot. Other adapter cards may be required to allow the computer to support new peripheral device.