Ok, we've gotten the very basics out of the way so let's move on to some other components of your computer.  This addition is going to cover both connections and components, and although these aren't usually a cause of problems, it's still good for us to understand their function and how they fit in to the grand scheme.  Please note that this is by no means an all-inclusive-list, and that I have tried very hard to keep this material as simplified as possible and have generally forgone my normal humor so as to keep the reading easier.  Because it is highly technical to start with, I may have failed here and there.  If there is technical information here that you don't understand and would like to, please feel free to contact me directly and ask.  I will answer you as quickly, and as simply, as I can.  Here we go:

Motherboard - Also known as the main board, logic board or system board; this is the main (and naturally the largest) circuit board in a computer.  It houses all the connections for the CPU, memory, HDD and Floppy disc controllers, expansion slots for sound, graphics and networking cards as well as other peripheral components.  This is the part of the computer that determines what CPU you can use (type and speed), the type and amount of memory available for installation and what peripherals you will have available to install.  Please consult your users manual or the Original Equipment Manufacturer (OEM) for the specifics of your motherboard before purchasing or installing any new components.  Failure to do so will, at best, cause you to sadly and dejectedly return your previously-exciting new purchase to the store or, at worst, damage the motherboard and the installed component beyond cost-effective repair.  In other words:  Broke, can't fix, need new one.

BIOS - The Basic Input/Output System is almost universally a chip (or chips) installed on the motherboard that is  loaded with firmware (software that is integral to the system's hardware configuration).  The firmware gives the computer the initial commands necessary to ready it for the operating system to load, execute and assume the functions of the computer.  It stores the correct time, HDD, Floppy drive, mouse, keyboard and other peripheral information; more recently, it has assumed the role of power and thermal manager, as well as controlling hotswap devices such as USB (see below).  It has for some time now been flashable, meaning you can download a patch or upgrade from the OEM that will upgrade the BIOS to fix bugs and give it enhanced capabilities.

Expansion Slots and Connections - There are several different slots and connections that may be available inside or outside of your computer, with the choices mostly dependent on the age of your PC.  These are the interfaces that are used to give you sound, graphics, network connectivity, external and internal storage options (HDDs, CD-ROM, etc) and to connect the other hardware in the computer to the motherboard.  The following is a list of the most popular in the last 20 years:

ISA (and EISA) - The Industry Standard Architecture and it's big brother, Extended ISA were developed in 1983/84 (respectively) and were the expansion slots and cards of choice up to the advent of PCI.  The main problem that you encountered with this architecture was the fact that it was very rarely plug-n-play (and if it was, it was commonly called plug-n-pray), meaning that you had to configure the card and your system manually to recognize and utilize it.  This card type has been squeezed out by more user friendly architectures such as PCI, AGP and now PCIe. The transfer rates for ISA was 4.83MB/sec and EISA was 16.85MB/sec.  The picture at left shows a slot incorrectly labeled as ISA; it truly is an EISA, as an ISA would be approximately half the length.

PCI - The Peripheral Component Interconnect was introduced in 1993 (around the same time as the Pentium architecture) by Intel as the replacement for ISA/EISA.  The main difference that users benefited from was the fact that they could plug-n-play; install the card, turn on the computer and have the BIOS and the operating system configure the card automatically.  Another benefit was the fact that these cards utilized a much faster interface with the motherboard than ISA/EISA did, allowing the computer to run faster with transfer rates varying between 133.33MB/sec up to 533.33MB/sec.  99.9% of computers today have PCI as their main expansion slot architecture.

AGP - The Accelerated Graphics Port (or Advanced Graphics Port) is a dedicated slot for graphics cards and was introduced by Intel in 1997.  It is much faster than PCI when dealing with graphics rendering (for several reasons that I won't cover here…way too technical), and has been the de facto standard for graphics until recently, with the advent of PCI Express.  Transfer rates vary from 266.66MB/sec to 4.266GB/sec.  If you decide to upgrade your graphics card and your motherboard is equipped with an AGP slot, be sure to consult your users manual or take it to a professional.  There are several versions of AGP and if you get the wrong one, it either won't fit or it could potentially damage your system.

PCIe - PCI Express is an updated interface that utilizes PCI programming concepts, but is not akin to PCI the same way that ISA and EISA were to each other.  EISA expansion slots were backwards compatible with ISA cards, meaning that you could use a "legacy" ISA card in an EISA slot.  This is not the case with PCI and PCIe.  PCIe has already become the industry leader for high end graphics and for new Giganet ethernet cards (see description below) because of its high-speed bus, but is quickly being adapted to sound cards and other peripherals.  PCIe is capable of delivering and accepting up to 80GB/sec, greatly increasing speeds within your computer and across a network of computers.  This is a very new architecture, and is only seen in computers manufactured in the last two or three years.  As you can see from the various pictures, including the one at right, it is important for you to know what connections you have available before you buy an upgrade card for your PC.  Most of the time it's merely an inconvenience when you get the wrong card; other times, you'll find that you can fit the wrong card into a slot with disastrous results (this is especially true with memory modules and AGP cards).

PATA -The Parallel Advanced Technology Attachment (ATA) interface (commonly misnamed IDE [Integrated Drive Electronics]/EIDE [Enhanced Integrated Drive Electronics]) is used for connecting HDDs, CD-ROMs, CD-R/WR drives, DVD-ROMs and DVD-R/WR drives to the motherboard.  It is a legacy interface from the old Industry Standard Architecture (ISA), and uses an 18 inch ribbon cable to attach the drive to the motherboard.  It is capable of affixing up to 2 devices (e.g. 2 HDDs) per cable, 1 as a master drive and 1 as a slave drive, each sharing bandwidth with the other.  Transfer rates run from 33MB/sec to 133MB/sec.

SATA - The Serial ATA interface is the successor interface for the PATA interface.  The 2 biggest upgrades over PATA is increased transfer rates and the dropping of the master/slave device interface, giving each drive its own cable and dedicated bandwidth.  Transfer rates today start at 150MB/sec and run through 300MB/sec.  This is a relatively new interface, and is only found in computers made after 2000.

PC Cards - Also known as PCMCIA (for Personal Computer Memory Card International Association) cards or CardBus; Portable Computer Cards are used almost exclusively in laptop computers in a similar way as expansion cards are used in a desktop computer.  Initially designed by IBM in the early 1990's as a memory expansion card slot (Type I), further advancements have been made with Type II (mainly phone modems and Network Interface Cards[see explanation below]) and Type III (which include external storage devices like HDDs and the like).  Most laptops today have Type II card slots solely, due to other memory and external storage device connections such as USB and, to a much lesser extent, FireWire coming in to wide-spread availability.

Serial Port - Also known as RS-232 and RS-422 (RS stands for Recommended Standard); this legacy port can  still be found on computers today, but there are almost no components available to use it anymore.  It's original function was to connect a phone modem to older computers, but it has also been used to connect printers, mice and keyboards.  This port is unidirectional, meaning that data can either flow out from or flow in to the computer; flow in and out at the same time is not possible.  Transfer rates run from a criminally slow 960B/sec (you read that right, 960 Bytes per second.  You'd get a ticket for going that slow on the information superhighway!) to 1.25MB/sec

Parallel Port - Also known as IEEE-1284 (after the standard developed by the Institute of Electrical and Electronics Engineers); this legacy port can also be found on most computers today.  Developed by Centronics in the 1970's as a connection for its printers, it soon became the industry-wide standard with the IEEE officially blessing it in 1994.  Because of it's high throughput, it's use blossomed over the years to include external tape and HDDs, scanners, and networking equipment.  There are still components available (mostly printers) but they are rapidly being supplanted by faster, cheaper USB devices.  At the time, this was a very fast connection which allowed bi-directional data transfer, meaning the device and the computer could send information to each other simultaneously.  Transfer rates for this port are up to 1MB/sec

USB - The Universal Serial Bus was initially designed to complement FireWire and was implemented mostly on user input devices such as keyboards and mice.  Because of FireWire's high cost, most computer manufactures (except for Apple, Dell and Sony) went exclusively with USB, and as such hundreds of other devices were developed.  Now the de facto industry wide standard, most new peripherals such as printers, external hard drives and flash memory "sticks", digital still and video cameras, cell phones, scanners and hundreds of other consumer electronics are all USB compatible.  Two of the biggest benefits of USB for consumers is the ability to hotswap (connect and disconnect a peripheral without powering the computer off), and the ability to easily daisy chain multiple devices (up to 127 individual devices at once!) together.  Transfer rates run from a very slow (by today's standards) 192kB/sec up to 60MB/sec.

FireWire - Also known as iLink or IEEE-1394; FireWire was mainly an Apple Computers invention.  Designed for  high speed transfers of large video, photo and audio files, it was hoped that this standard would become the serial bus of choice by computer and peripheral manufacturers.  Although it was initially much faster than USB, it was because of it's high cost to license (Apple holds the rights to the FireWire standard) that most manufacturers opted to go with the cheaper, albeit slower, USB standard for broad release to the public.  In recent days, even Apple has moved towards USB, with its newer generation of iPods switching from FireWire to USB connections.  This standard is also hotswappable and has the ability to daisy chain multiple devices together (up to 63 different devices).  Transfer rates run from 12.5MB/sec to 100MB/sec

Graphics Card - Also known as a Graphics Processing Unit (GPU); As the name clearly describes, this card is the workhorse that renders all of the graphical interpretations of your programs and transmits that information to your monitor.  Because they have their own on-board processor that is specially designed for this purpose, they are infinitely better at rendering graphics than the CPU is.  Hence, we have seen huge leaps in 3D graphics in computer games, as well as the processing and rendering high resolution graphics from digital cameras and video recorders.  There are 2 types:  Dedicated and integrated.  Dedicated graphics cards are typically add-on cards and have on-board memory that is used solely for graphics rendering, helping to alleviate the burden from the main system memory, or RAM.  Integrated cards are typically hardwired to the motherboard and do not have their own on-board memory, instead utilizing the main system memory.  Please remember that what determines which card you have is whether it has on-board memory or uses the system's main memory.

Sound Card - An expansion card that can take input from and send output to audio devices such as speakers, headphones, music players and MIDI (Musical Instrument Digital Interface) devices among other things.  Computers started featuring sound cards as standard equipment in the early 1990's, and have since gone from very basic 2 speaker devices to high-end 5.1, 6.1 and even 7.1 surround sound stereo capable devices.  The way that the hardware (sound card) and the software (the OS) meet up to produce sound is by means of software CODEC's (which stands for Compression/Decompression). These codecs are installed into the OS and give the sound card the proper "language" necessary to reproduce/playback specific sounds and files.  For instance, Windows has specific codecs for MP3 music playback (so you can play your favorite songs on your computer) and for MIDI device sound production and playback (so you can be the musician).  Most sound cards produced after 1993 also have included on them a joystick connection, for use with some computer games.

Telephony Modem - Modem stands for MOdulate/DEModulate, and telephony is pronounced tel-EF-ony (emphasis on the EF); this is the everyday modem that has been standard in PCs since the early 1990's, but these devices were originally designed by IBM in the 1950's to help connect geographically distant computers for the US military on secure lines, and were slowly brought in to consumer use in the 1980's thanks largely to Hayes and US Robotics.  This expansion card uses a regular telephone line and cable with an RJ-11 (RJ stands for Registered Jack) connector on either end to connect your computer to other computers, usually through a Bulletin Board System (BBS), or to the internet through a local Internet Service Provider (ISP), via the telephone company.  It accomplishes its task by turning binary language code (very large series' of 1's and 0's) in to sounds (modulation) that are carried over telephone lines, and decoded back in to binary in the proper sequence on the other end (demodulation).  Typical throughputs (or download/upload speeds in kilobits/second) on modems since the early 1990's run from 14.4kBs/sec to 56.6kBs/sec.

Network Interface Card (NIC) - Also known as an Ethernet Card; this is an expansion card that uses (typically) twisted-pair network cable with an RJ-45 connector (about twice the size of a telephone jack) on either end.  They are used to connect your computer to a Local Area Network (LAN) which can be in your home or office and/or to Wide Area Network (WAN) like the internet or a large, geographically separated corporate network.  NICs are capable of transferring data at 10MB/sec, 100MB/sec or with new Giganet NICs, 1GB/sec (or 1000MB/sec).  Each NIC has a unique 48 bit identifier, called a Media Access Control (MAC) number that is used just like the address on your house.  We will cover MACs and basic networking terms and protocols in a follow-up blog specifically suited for that purpose.

Floppy Disk Drives (FDD) - Most people will remember these drives as a piece of their computer that they rarely, if ever used .  Because of the advent of optical and flash drive technologies and the ever increasing size of applications and related data, these drives have been almost entirely supplanted.  Out of fear of leaving consumers with no way to recover from a catastrophic operating system or HDD failure, most manufactures continued to include a floppy drive on most of their systems until recently.  Now days, optical drives and flash memory sticks are bootable (can be loaded with control commands that take over when the BIOS has completed it's initial startup, and accessed in lieu of the HDD during initial power on), and can be used easily to recover from such instances, so more and more manufacturers are removing floppy drives entirely.

Optical Drives -  There are as many technologies and corresponding names as there are manufacturers.  With most drive makers creating hybrid drives that read and write to a multitude of varying disk formats, the format wars created by the competitors has left end users largely unaffected, so for our purposes here I will forego an in-depth explanation of each and just refer to them from here on out as such:

CD-ROM - Only reads CDs.
CD-R - Reads and records to CDs.
CD-RW - Reads, records to and can re-write CDs.
DVD-ROM - Reads CDs and DVDs
DVD-R - Reads and records to CDs and DVDs
DVD-RW - Reads, records to and can re-write CDs and DVDs

Because of their speed, storage capacities and their corresponding media's resistance to damage, these drives (with the help of USB flash drives) have all but run Floppy Drives off of the personal and business class computers and DVD drives have become the de facto standard for most machines made today.  The drive makers are still upgrading (now we're into high definition) and battling it out for standardization, with a large group including Pioneer, Sharp and Sony marketing the Blu-Ray format heavily, and DVD Forum lead by Toshiba, Microsoft and HP trying to take the market with DVD-HD.

Wow!  That turned out to be a much longer set of descriptions and explanations than I had originally planned on (it took me 3 days to get it written up and formatted properly).  I apologize for that, but if you can wrap your head around all this, we're ready to move on to bigger and better things like basic networking (including how it ties in to the internet), computer security, and more.  Stay tuned for future installments!

Steve@Dall-tech

**I also want to take time to state that I did use Wikipedia to make sure I got the descriptions/explanations right, and to get the proper dates and transfer rates, but the writing/wording is all mine.**