Home Computing and More Lesson 4
Computing for Beginners Lesson 4
As we learnt in an earlier lesson, EVERY device has its own digital identity, its MAC, Media Access Code or address. Just as every human being is unique and society has rules for identification purposes etc., so our devices differ independently.
This all makes perfect sense and in a similar fashion, we all live in different places, at different addresses and we have systems that allow communication between our homes no matter where we live in the world.
It stands to reason that every different page we encounter on the Internet, lives at its own, unique address. This locater address is called a URL – a Uniform Resource Locator.
There is a box on every webpage where this URL is displayed and you will no doubt have seen them, they look like these examples that follow: www.shoobridgefunerals.co.uk but, could appear as:
We talked about sending mail over the Internet and the fact that we have agreed protocols to abide-by to enable communications? Similarly, URLs follow protocols, in this case, http or, Hypertext Transfer Protocol and in this format, the protocol is another text protocol as opposed to a speech protocol. I mention this because all URLs are dealt with in this fashion for our purposes BUT, it is not unknown and in fact, it is quite common to see the URL defined as 
The ‘s’ is extremely important and can often be displayed in a green font colour.
With browsers, in-built security measures are provided by the individual browser company. Due to ‘hacking’, we suffer the indignation of fixing a crime after it has occurred, been committed or, identified.
IT (Information Technology) personnel and programmers usually manage to ‘fix’ these problems and update their security measures accordingly. One measure of defence is known as SSL and whilst the acronym stands for Single Socket layer, we are not going to delve into this area of technology but you may come across the term as well as, encryption.
Whenever we wish to access extremely pertinent financial information, make a payment online or perform online banking actions, we HAVE to be aware that, there is one more ‘layer’ of security, which can be employed. This ‘extra’ security is again provided by the browser ‘people’ but is instantly recognisable by the URL - 
The ‘s’ stands for SECURE – Hypertext Transfer Protocol Secure. If you are performing any type of financial transaction or viewing an online account and the ‘s’ is missing from the URL, you should NOT continue under any circumstance!
Similarly, you can NEVER be complacent. You must think like a hacker: if you are going to interfere in any way with anyone or their information, you are going to hit them where it hurts – by disrupting their ‘paper’ lives or their monetary situation.
If I ever give you one piece of advice, and I will give you many over the coming lessons, ALWAYS read what is on the screen, in front of you! Don’t be paranoid but never take things at face value. Just because it is a computer, do NOT trust that which you are seeing WITHOUT first considering perspective. Just because it is written on the screen in front of you does not make it true or a fact. Who, or what, is behind what you are viewing? And Why?
Let me give you an answer or, scenario: we have just learnt about URLs and Secure URLs, we can see them on the screen and we ‘know’ they are secure so where, if you were a hacker, would you attack me, the computer user at the end of the line?
Well, if I could convince you into believing you were somewhere but I could actually take you somewhere else, that would be interesting?
If I could ‘hack’ your URL for example? Let’s take a for instance outside of the computer:
If you go shopping in Walmart but for one day, I kidnap all the staff and bring my own people in and we serve you all day long and you pay for goods we don’t have but will send you or take a rain-check on, we walk away with all your money and disappear, overnight. You now have absolutely no redress and your money has gone. This may not be the best analogy but you take my point – if I take over your URL somehow and redirect you to my site which APPEARS to have that URL, you can top up my bank account all day long – thank you very much!
In a similar way, if ANY email asked you for personal information to do with security, your log-on details or passwords, they are malicious - ONE HUNDRED PERCENT! so, DELETE them immediately.
There are NO free lunches out there. There are NO fortunes coming your way by gift or winnings, no holidays without a catch and, no matter how tempted you are, DON’T!
If you do? You may want to recall this advice before ‘crying’ about your losses – you have been warned – this practice is called Phishing and that is accurate terminology.
If you are in any doubt, there are websites which clearly state all the scams and we have all heard of Nigeria. Urban Legends, Snopes are two such websites so you DO have control and, responsibility – if it’s too good to be true, it’s a SCAM!
Before we leave emails, again, you WILL receive lots of emails from sources that are totally unfamiliar to you. This is quite ‘normal.’
The Internet exists because of money. Money is generated by the result of sales from advertising and the cost of companies to actually advertise on the Internet.
Some access is provided by consumers when signing-up to newsletters. Some is provided unfortunately, inadvertently, by your friends and families (emails). Similarly, when you access wi-fi hotspots in airports or fast-food chains, you often have to sign-up to gain access to the ‘free’ wi-fi. Guess what? You just signed-up! Of course, you can unsubscribe if you remember and most companies will honour your, ‘unsubscribe’ request but ultimately, all these different methods are recorded or logged and ‘mail-out’ lists are compiled by companies operating, effectively in the background.
These lists are ‘sold’ to companies for direct emails access to your email address, to you the consumer, to entice you into buying their products.
Cleverly, this forwarding type of operation is so ‘mechanically’ (digitally), easy it is performed by unmanned computers, robotically.
ISP recognise lots of malicious and nuisance types of email, commonly known as spam or junk mail and filters it out at their server level, never passing it on to a ‘wiser’ consumer client base but not everything is recognised and ‘junk’ or ‘spam’ is subjective – sometimes we want notifications and newsletter despite what they may contain additionally – we can ‘train’ our own mailboxes accordingly – we have options.
We will be dealing with search engines presently but everybody has heard of Google without a doubt? Google searches the Internet for sites and locations for us along with other giants from Microsoft like Bing. Yahoo is another big player and they all perform multi-functions – they track our Internet habits!
Shopping, research, software, music, videos, good habits and bad habits are ALL recorded, logged or noted in some fashion. Little tracking devices are attached behind the scenes within the programs called ‘cookies’ and surfing is almost impossible without ‘cookies enabled.’
This is not ALL bad. There are numerous good reasons to track us. We like the idea that criminal activity CAN be tracked. We are pleased that paedophile prosecution can be supported by computer file evidence; some people might not be happy to know their pornographic habits are tracked but once child-pornography is the subject, opinions change.
The point is, there is good tracking and bad tracking.
From a shopping perspective, Google, who receives money from their advertisers, send us offers and special offers that reflect our earlier shopping or surfing habits – we are being selectively targeted. (Remember that MAC address?)
Companies like Walmart, Superstore and Tesco simply love us shopping online. They target us with coupons we are likely to use and not ones we are not. They tempt us and continue the subliminal onslaught ferociously. We are constantly being monitored in some way; by our credit and debit card usage, where we buy our petrol/gas and how often – it is laughable when we talk about big-brother as the government when the government has very little interest in our daily habits unless of course, terrorism is involved; big-brother is/are, those institutions we have actually welcomed into our lives! Openly!
In summary, there is no escape! LoL. We are or can be, our own worse enemies or best friends. We actually have lots of choices hence my advice to read the computer screen and examine just what exactly we are reading and why then, how could anyone else could use this information or data to good or not-so-good if not, bad?
The digital age is upon us – like everything, progress is subjective to the recipient. For every progressive step forward, we tend to ‘give-up’ something else, even our freedom.
We always have responsibility, choices and, consequences – it’s life.
Somewhat out-of-step, I am going to explain a little about digital information.
If you don’t know the shape of a sine wave (analogue), it doesn’t matter. Suffice it to say that we are in a digital age and though sine waves are generated electrically quite naturally by scientific processes, we have learned how to change this shape into a square wave form as mentioned in an earlier lesson.
The square wave suits our purpose tremendously as we can break it down into minuscule divisions and attach information to those divisions as we decide. This can take the form of text data, music data, video indeed, ANYTHING we choose, literally.
When we initially started breaking down or dividing the wave form, advances were slow and for our purpose, let’s imagine breaking a single unit into 32 parts or, bits. The more clever we got, the more we sub-divided; 64 bits, 128 bits, 256 bits for example. The expansion is virtually, exponential.
We can also vary this square wave by two methods; we can make the wave travel faster and also make it a bigger volume. Now, the sky is the limit well, sound is and no doubt, light speed will come in the form of laser technology.
Add to this a little process called compression. As with our MoDem, our modulator – demodulator, we can attach things (transmit) to carrier waves so long as we can devise a method to interpret the information at the receiver end or simply code it for transmission and decode it for reception and, we can.
If you observe my writing, the text above, it is easy to see that the space I use is extremely, wasteful. IfIwroteinthisfashionwithnospacescommasorperiods It would be confusing to you. Digital information is NOT confusing to a digital medium certainly if once it is received, we can, decode it. I can further this cause by making the size of the letters a third of what they are currently; this process is a simple illustration of, compression; there are numerous methods of compression and they are ‘media’ targeted.
Media simply refers to things like music, video, SMS – text messages and so on. The way we compress photographs is different to how we compress video and music.
Some familiar forms of compression, as with music are MP3 and MP4. Video files depend where, to a certain extent, they were created – a Windows application will give rise to a .wmv file whereas an Apple constructed video would likely be an .avi file. There are indeed so many compression mediums that converters have been created in software programs in order for us to view each other’s creations.
If we look at a camera specification, we see that they are classed on one front by their capacity to take detail, so many mega-pixels. The larger the number, the better the capability to capture the detail but the slower the process. For professionals that depend on advertising or photography for a living and possibly need to enlarge a photo to a poster size for an advertising campaign, this detail is very important.
For the average person, such a photo (.raw) serves no other purpose than to hinder our experience by slowing down our camera’s processor. There is, of course, a solution to this problem – compression. Again, there are numerous types of compression but the most popular by far in use today, is JPEG - Joint Photographics Experts Group.
I reminisce at CDs. A large disc containing music and the most popular form of replaying such since the cassette tape. LPs; EPs; 45RPM; 33RPM; 78 RPM – in short, Vinyl, have all but disappeared too?
MDs? What the heck are/were they? An MD is the equivalent of a ‘compressed’ CD.
Our audible range, as we know, is limited. We do not hear the low frequencies and we do not hear the high frequencies and there are more high frequencies we don’t hear than compared to the low ones however, our CD marketers told us that CD’s were what we needed and CDs, we duly accepted. The MD or mini-disc however was extremely clever. It essentially recorded and reproduced ONLY the frequencies we can actually hear and cut-off, the rest.
As with VHS as opposed to BetaMax or Phillips 2000, and Blueray as opposed to Red laser reproduction mediums, the marketers decided what was best for us and we adapted, CDs despite this obvious waste of inaudible information.
Compression is the sensible way to reduce and speed up everything we want these days so long as we can maintain quality and speed. We therefore encode it then decode it. With security, we encrypt and decrypt.
You can see the limitless and infinite variety of measures that we can attach and detach to our square wave form; this was not possible with analogue configurations.
As I have indicated, for every piece of information I give you, birth is given to ten pieces of detail I am not dealing with but, like any expert student, there are courses designed for information technology at various levels; my aim is to get you ‘street-smart’ to a practical level of understanding that you will be comfortable with in our society and to that which offers practical help in your everyday practice using a multiple range of IT devices.
Computers have also altered over the years. Apart from processor speed increases, we have taken a side-ways step. Wouldn’t it be nice to have one home computer which encases two processors, three processors or four processors even?
Let’s accept one thing first - for no reason explained here. In a digital world, numerals tend to double in quantity from the whole number; therefore we have values like 1,2,4,8,16,32,64,128,256,500 and 1000 – we don’t deal in 3,7,9’s etc..
Taking a small step backwards, processors would be 1, 2 or 4 in number then 8 of course and so on.
Practically speaking, having 4 processors would be complicated and costly so what if we split one processor into two cores or four cores?. Of course, we would need to give them more ability to operate in conjunction and separately so if we could increase their resources, RAM – Random Access Memory, we could reduce our impatience at the keyboard and on the screen and get results quicker and more efficiently. Welcome to modern computing.
This would have been almost unheard of 15 years ago and almost beyond our wildest dreams and that’s just computers; we are also developing mobile devices at the same levels hence, LTE (media downloads) and Smart phones.
To complete this lesson, computer processors have also increased in efficiency and one of these advances is developing processors that can deal with the ‘bit’ technology of the data we are interested in. For the longest time, our processors were designed to cope with and process 32 bit technology. Ten years ago, the design was 64 bit which is perfectly adequate for our present needs though doubtless, a no-limit situation is developing constantly.
Incidentally, processor temperature is a vital factor in computer processing. Reducing component size is all well and good for portability and to enable us to facilitate multiple computers in the same location but power and heat are two of the biggest problems we will encounter.
Making a computer more powerful but smaller means increasing the problem four-fold or, exponentially (not quite an accurate definition). Power means heat. If we could reduce the heat and increase the power and decrease the heat again, we could move into the realms of a ‘super-computer!’ Not for home use of course but as a study of interest, that is where the industry is heading and, they exist already.