But if you're left stumped by what goes where - and what all those cables do - this handy guide covers the common cables seen in many modern computer systems, so the next time you encounter each one, you can not only plug it in with a little more confidence, but hopefully you'll also know exactly what it's there for.
Centronics Connector
The early 'Centronics connector' was the first widely adopted parallel port, introduced for the first time in 1970, and in many ways set manufacturers on the road towards industry-standard ports like USB. Developed by Centronics as a one-way connector to carry data from computers to peripherals such as printers, it was so successful that its name became synonymous with that of its manufacturer, and many people still use it today.FireWire
FireWire is a brand name for the IEEE 1394 connector - also known as i.LINK in Sony devices, and Lynx in Texas Instruments products. It represents a fast audiovisual connection, with a bitrate of up to 400 MB/s (3,200 Mbps), but never quite gained the widespread popularity that USB connectors have managed in recent years.Line-In
Even if you've never hooked up a computer sound card, you may have seen a line-in socket on a hi-fi or home entertainment system, and they all do basically the same thing. That is to allow sounds to be transmitted to the computer - usually from an instrument or recorded source, rather than via a microphone, as voice signals are typically sent to a separate microphone socket with the ability to boost the volume of the input.Parallel Connector
The generic name for the Centronics connector, later parallel ports supported two-way traffic, allowing them to be used not only to send data to printers, but also to receive images from scanners.In essence, they were the hardware development needed for multi-function printers with scan, print, fax and copy capabilities to be introduced.
PS/2 Connector
Another connector that most people will have encountered at some point, PS/2 is the small, round connector found on keyboards and mice around the turn of the millennium (you may have seen colour-coded purple and green connectors in particular, during the protocol's later years of popularity).It was introduced by IBM as part of the Personal System/2 line of personal computers in 1987, although serial mice were still used for some time after that - and these days you're more likely to see USB mice, as the PS/2 connector has finally started to dwindle in popularity after a decent run as the dominant option.
RJ45 Connector
Largely the preserve of London IT support providers like Conosco, and their counterparts elsewhere in the country, the RJ45 connector will be familiar to you if you've ever set up an Ethernet connection - even if you never knew what the connector itself was called.You may see it used to connect computers directly to one another, but more often they'll be linked via a central hub or router - and the wiring of the cable itself can be different depending on whether a hub is to be used or not, as 'straight through' and 'crossover' RJ45 cables are slightly different from each other.
RS-232 Connector
The RS-232 is the technical name for a serial connector, one of the earliest and most long-lived ways to expand the capabilities of a computer beyond the confines of its case. With a serial port, early PCs gradually gained mice, modems, the first peripherals, external power supplies and extra removable storage - revolutionising their potential and allowing 'upgrades' to be made on an as-and-when basis, rather than needing to crack open the case each time you wanted to get online or increase your disk space.SCSI Connector
The Small Computer System Interface, or SCSI, never really caught on in home PCs, although it's more commonly found in server systems and was also used in Amiga and early Apple Macintosh systems. When it comes to pronouncing the acronym, think 'scuzzy', not 'sexy' - and don't be fooled by the 'small' part, as SCSI's use in server RAID arrays means it can often be found in very large computing installations indeed.Serial Connector
As mentioned above, the RS-232 serial connector was a gamechanger in the development of PCs, and is a true ancestor of modern connectivity protocols that still survives to this day for basic functions in research laboratories and universities all over the world.S/PDIF
A five-letter acronym that's almost impossible to pronounce as a word (sip-diff, maybe?), S/PDIF is short for 'Sony/Philips Digital Interconnect Format' and carries digital audio data either by a coaxial cable, or via a fibre optic with TOSLINK connectors at each end (short for the much more concise 'Toshiba Link').You might think fibre optics are fairly new for home entertainment systems, but S/PDIF has been around in one form or another for three decades, and is showing no signs of losing popularity just yet as high-definition formats become commonplace in the home.
USB Connector
Last, but by no means least, Universal Serial Bus (USB) connectors not only link the vast majority of computing devices made for the modern market; they also link the family trees of many of the outdated connectors described above. Capable of receiving and transmitting data, as well as powering smaller devices - and with the option of expanding the number of USB connections on a system using an external hub - it's easy to see why USB and its smaller siblings, mini and micro USB, have earned their place in electronics history.While nothing lasts forever, it's hard to imagine USB going anywhere just yet, with its position secured each time a faster, yet backwards-compatible update of the USB protocol is launched, such as the blisteringly fast 5 Gb/s (625 MB/s) of the current USB 3.0 standard.
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Conosco is a management team with over 200 years experience in IT support; a vibrant force in the world of IT support and strategy.