USB stands for “Universal Serial Bus”

This is not to be confused with “USP”, which is a marketing term meaning “Unique Selling Proposition” and describes what might be a small, insignificant, difference between one product and a competing one.

USB is a type of connection that was designed to be suitable for connecting all types of external items (“peripherals”) to a computer.

USB ports (the “socket” part) are much smaller than the parallel and serial ports of earlier generations of computers. Also, you can connect a device with a USB cable without having to re-start the computer to get it to recognise the device you’ve just plugged in. This is called “hot plugging”.

The most common type of USB connection that connects peripherals to a computer is USB Type A. This is the familiar rectangular connection that will only fit one way up. We are now on the third generation of USB connections – each one being faster than the previous one. USB connections are “backwardly compatible”, meaning that if you connect a later generation device to an earlier generation port then everything will work – but at the lower speed of the earlier generation port or connector.

If you are connecting a mouse, keyboard, or printer, the speed of the USB connection doesn’t matter much. If you are connecting an external hard drive then the speed does matter. A new portable external drive will almost certainly have a USB3 connection, so connect it to a USB3 port on the computer if at all possible. You can tell if a port is USB3 as it will either be partly blue when you look directly at it or it will have “SS” (for “Super Speed”) written very close to the port.

USB plugs

USB C, USB2 A, USB3 A, micro, mini, USB B

Printers have traditionally been connected using a different plug at the printer end. This is a square plug with two edges chamfered off. Once again, the plug can only be inserted into its port one way. This type of connection is called USB Type B. Having said that, most people prefer to connect their printer wirelessly these days, so the USB connection is redundant.

Lots of new laptops now feature a new generation of USB connection called Type C. This is much smaller than Type A and can be connected either way up. You can buy an adaptor to connect a Type B plug into a Type C port. For that matter you can get all kinds of adaptors for changing one type of USB port or plug into another. Go to Amazon, for instance, and type “USB adaptors” into the search box.

The end of a USB cable that connects to the device might be much smaller than the end connecting to the computer. An older design of this was called “mini USB”. The current design is even smaller and is called “micro USB”. Once again, the cable can only be connected to the port one way up.

There is another type of USB connection – just for Apple devices such as iPhones. This is called the “lightning” connector and it is used instead of the mini USB and micro USB connection of non-Apple devices. The other end of a “lightning cable” features a standard Type A plug.

USB coffee warmer

USB coffee warmer

USB connections allow data to be transferred between devices, but they can also transfer power as well as data. 2.5 inch external hard drives, for instance, are powered by the USB connection as well as the data transfer taking place along the USB connection. There are also some devices (mini fans, for instance) that are connected via USB simply to power them – ie with no data transfer taking place. You can even get a USB-powered gizmo that keeps your coffee warm (if you don’t mind risking knocking your coffee over into your keyboard).

I hope this helps to clarify a rather confusing area. The confusion is mainly caused, of course, by the fact that things change and improve over time and the changeover is never neat with a cut-off date. We always have lots of “generations” in use at the same time. Plus ca change…

If you’d like to know more about this utterly fascinating (!) subject, then you could try https://www.techdim.com/usb-2-vs-usb-3-use-usb-3-0-rather-usb-2-0/

This is the second in a series of three blog posts on the subject of buying a new computer. If you would like to receive all of the information now and in one go, just drop me an email and I will send you a pdf file.

Storage

Laptop Hard DriveSolid state drives (that work more like USB pen drives than traditional hard drives) are replacing hard drives, but the changeover is taking many years. They make a machine much faster to boot up, switch off, and operate, and are definitely a good thing. However, they are still more expensive than traditional drives. This means that you either get a smaller drive for the same money or a larger drive at a higher cost than a traditional drive.

This, in turn, means that if you buy a machine with an “average” size of SSD, it is likely to be 250-500gb. This is only a one eighth to one half the current standard size of traditional hard drives (1tb or 2tb – where 1tb = 1000gb). Now, 500gb is plenty big enough for a lot of people, but if you have large photo, music, or movie, collections then 500gb will almost certainly be totally inadequate.

To overcome this problem, some machines have a small SSD to store Windows and run the programs, and a large traditional drive to store large amounts of data. This is fine as long as you know how to access different hard drives. This is not difficult if you are reasonably comfortable using Windows/File Explorer, but it can be problematic otherwise – especially when the default behaviour of Windows and the programs you use is to try and store everything on the SSD and you don’t know how to address the hard drive instead.

There is also something called a “hybrid drive” that contains elements of both drives.

My recommendation is that if you are not sure of these complexities then opt for either an SSD or hard drive but, if it’s an SSD drive, then check that it will be large enough for your needs.

CD/DVD Drive

CD/DVD DriveLaptops often do not have these any more, although they are still fitted to new desktop computers. Their use is diminishing as more programs and content are downloaded or streamed direct from the internet. Also, removing them from laptops saves weight and allows the whole machine to be sleeker.

Their lack need not be a huge problem as external CD/DVD drives (that plug into USB ports) are widely available and only cost £15-£30. Search Amazon for “external DVD drive”.

USB Ports

USB3 portsMost standard USB ports are now “USB3”, but you may still find a machine with a mixture of USB2 and USB3. The difference is speed, but it will probably only really be noticeable when copying or streaming large amounts of data to/from an external drive. Nevertheless, USB3 is definitely preferable to USB2.

Possibly of more concern is that laptops (but not desktop computers) tend to have fewer USB ports than previously. Whereas 3-4 USB ports used to be the norm, 2 is now more likely on laptops. If you buy a machine with the new “USB C” connector, an adaptor can be fitted, if necessary, to connect devices with the earlier (standard) USB plugs. Search Amazon for “usb c adaptors”.

More USB ports (eg 4) is definitely better than fewer (eg 2). You can buy USB hubs to extend the number, but these get unwieldy if you regularly move a laptop, and you shouldn’t try to connect an external hard drive via a USB hub as there might not be enough power. Search for “USB hubs”.

You can tell USB3 ports as they are partly blue inside. Alternatively, they may have “SS” written alongside. The ports in the illustration above are marked in both ways. USB2 ports are black inside.

Ethernet Port

Ethernet Port and CableSome laptops no longer offer an ethernet port (otherwise known as a LAN port or RJ45 port) for a wired internet connection. Without this, you can not connect your machine to the internet using a cable from your computer to your router. Instead, you have to rely on wifi. Actually, this is not strictly true as you can buy an adaptor that offers an ethernet connection via one of your USB ports, but this may not be desirable as it uses one of your precious USB ports (but USB hubs that include an ethernet port are available. Search for “USB hubs with ethernet”).

Screen Size

Screen Size MeasurementThe most popular screen size on laptops is still about 15.5 inches, but there is now an almost continuous range of sizes available from 10 inches to 17 inches. If you are buying a laptop as your “main” machine, be very wary of buying one with a screen size (and keyboard) that might prove too small for comfortable all-day use. Personally, I would probably consider 13 inches as the smallest screen that I would like to work on all day and every day. Screen size is always measured diagonally across the actual screen area (ie not including the surrounding bezel).

If you are buying a standalone monitor (for use either with a desktop computer or as an external monitor for a laptop) then the bigger the screen the more comfortable and convenient it is in use. Alternatively, there should be no problem re-using an existing monitor with a new computer.

Touch Screen

Touch ScreenMore and more screens are now “touch-enabled”. This applies both to standalone monitors and to laptop screens. Expect to pay just a bit more for touch screens. If you anticipate wanting to use a pen directly on a screen (eg for editing photographs, sketching, or handwriting notes direct to the screen) then you do need a touch screen.

2-in-1 Laptops

2-in-1 laptopThis refers to laptops that can also function as tablets either by removing the keyboard entirely (as with the Microsoft Surface) or by folding the laptop in a given way. I can not imagine a 2-in-1 not having a touch screen but have not investigated this.

To be continued…

Years ago we used to have parallel ports, serial ports, scsi ports and goodness knows what else. Things are a lot cleaner and more straightforward now that most things connect to computers via a “USB port”. USB stands for “Universal Serial Bus“, strongly suggesting that this is a method for connecting all kinds of things via the same socket (or “port” as computer people call them).

Nowadays, we take USB ports and connections for granted, but there are a few things that it’s worth pointing out for the benefit of normal human beings (eg my own computer clients) who need to use them every day but don’t normally take any notice of them.

USB3

USB3 Ports

USB 3 ports are blue inside

USB3 is the latest “incarnation” of USB connections. The main improvement that we will notice is that USB3 is much faster. See this Wikipaedia article for more details. USB3 hasn’t yet completely replaced USB2 ports on new computers, but where they are present there seem to be one or two of them on a computer that also has one or two USB2 ports. As always with these things, I think we can get what my chemistry teacher used to call “delusions of accuracy” if we measure these things to the nth degree. However, I can tell you that transferring significant amounts of data (say 5gb or 10gb) to an external hard drive is definitely a lot faster with USB3 than USB2. Note, though, that it’s not enough to have a USB3 port on the computer: the destination (eg an external drive) also has to support it for the speed to be improved. It’s easy to tell which ports are USB3 as the inside of the port is blue (compared with black for USB2) – see photograph. USB3 ports are “backwardly compatible” so any USB2 device can be plugged into a USB3 port (and this will work at USB2 speed).

USB Sleep and Charge

Some computers now come with one or more USB ports that keep the power on when the computer is asleep or switched off. This means you can plug in a smartphone – or similar device that re-charges via a USB port – without having to keep the machine switched on or even plugged in (if it’s a laptop with its own battery connected).

Cables with Double Connectors

USB Cable With Double ConnectorHave you ever bought a USB-connected device that came with a cable that has two connectors at one end (see illustration)? If so, you may be wondering what the “spare” connection is for. Well, it’s just to ensure that the device is getting enough power from the computer it is connected to. Simply connect both of the “double ends” to ports on the computer. If you only connect one of the pair and the device doesn’t work then try the other. If it still doesn’t work then you definitely need both ends to be connected to get enough power to run the device. That can be a problem on laptops with limited USB ports. My old Samsung Q35 laptop only had 2 usb ports and they were on opposite sides of the case so the only way to connect power-hungry USB devices was to attach a USB extension cable to one port so that both ends of the USB cable were within reach. A bit messy and inconvenient.


Problems with USB Connections

The word “universal” suggests that you would expect a USB connection to work in any USB port. Generally speaking that’s true, but if you find that a USB-connected device doesn’t work it is definitely worth trying it in a different port. The port that didn’t appear to work for the first device may work with another device connected to it. I think this is all to do with the amount of power available to run the device and that some ports may be able to deliver more power than others (due to their position on the motherboard?) I’m not completely sure about the technicalities of this but I’m absolutely sure that it’s worth trying to swap them around. If you’ve got a lot of USB ports with lots of devices and you need to dis-connect them all (to pull the computer out from under a desk, for instance) then it’s well worth noting which device was connected to which USB port so that you can be sure of putting them back in the tried and tested configuration. When working on my own computer clients’ machines, I will sometimes take photographs of the connections before pulling things apart.

USB Ports Too Close Together

USB ports are often sited very close to each. This is usually OK if the connectors are of the standard size but some devices – such as wireless USB receivers and so-called “dongles” – are just too fat to place next to connectors in adjacent ports. The easiest solution in such situations is to buy one or more short USB extension cables and connect the fat device via the extension cable. The cheapest place to get things like this is at a computer fair but I wouldn’t expect normal people to frequent such places so you’ll have to bite the bullet and pay Maplin or PC World prices (or cadge one from me when I’m with you providing computer support or advice).

USB Hubs

4 port USB hub

4 port USB hub

These devices plug into a USB port and then allow you to plug two, four, or even more USB devices into them. In most cases they work fine, but try to avoid connecting external hard drives or CD/DVD drives into a hub unless the hub has its own power supply. This is because the computer may not be able to deliver enough power to the device if it’s going through a hub (that may also have other devices taking power from the same USB port). USB devices that are definitely suitable for connection via a hub include mice, keyboards, and cameras.

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Computer Support in London
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