You get to the checkout at the market, and the product you ordered 'on special' arises at the total price. The director needs to be called to fix it up, and what does he say?
'We have now been having troubles with the computer, it gets the incorrect value on some things.'
You devote a listing of addressess to your Word processor, and print off party invitations for...
Many have cursed their computer for taking things too literally! It's easy-to blame the computer when something goes wrong.
You reach the checkout at the market, and the product you bought 'on special' arises at the total cost. The manager has to be called to repair it up, and what does he say?
'We have now been having issues with the computer, it gets the incorrect value o-n some issues.'
You devote a list of addresses to your Word processor, and print off party invitations for in a few days. Should you fancy to dig up further on guide to rockwell trading, there are lots of resources you can pursue. You then realize that today's date has been introduced in the signature block - from the computer!
Perhaps you have heard the phrase 'Garbage in Garbage out'? Some body, sooner or later instructed the computer to complete what it did, It did not decide to screw you up intentionally. Computers can just only do what they're told, they are more sensible than Spock and they take everything literally.
We are planning to examine why they are so pedantic!
The entire world around us has many aspects which work-in exactly the same way as a computer. There are numerous types of opposites, for instance Up and Down, Left and Right, Forwards and Backwards. A light may be O-n or Off, maybe it is Night or Day. Yes or No? You can think of many others. This process of two possible states is called a Binary System, if it's not one, it ought to be the other.
A pc employs the Binary System to perform all its features, the basic unit, actually a vacuum tube, then a transistor, then a chip, is employed tens of thousands of times up to make the sum total unit. The light being On or Off which we stated earlier is controlled by way of a change. In the computer this move is really a transistor, which is either On or Off.
Now we get to the Math! Don't worry, it is very simple Math! In fact it is so simple we only total to 1. Therefore we count from 0 to 1 that's right, we could only have two states. (That's another thing pcs are pedantic about, they insist o-n starting at zero).
The Binary system is a Number System. You're knowledgeable about the system that has 10 numbers 0 to 9 (think like a computer 0 comes first). You can make up a variety of number systems for what-ever purpose you want. You almost certainly know about a dozen (12) and have also heard of a half dozen. If you have used your computer much you may have come across the Hexadecimal process. This one has 16 'numbers' 0-9and A-F. Yet another number system employed by computer people will be the Octal system which includes 8 numbers, 0-7.
Ok so how can we rely with only 0 and 1. Basic, in a similar way you count in decimal. The initial five numbers are OK, 0-9, but what next? We begin again but include a 1 making 10 or 'one, zero.' That gets us to 'one, nine' and we head to 'two, zero', and so on around 'nine, nine' then we again add a 1 to make 10-0 - 'one, zero, zero.'
If you have followed me to date you are ready for your Binary series, it's much easier. Starting off at zero we have 0,1 - and that's it. We follow the sam-e concept and include a 1, creating 'one,zero.' Next come 'one, one'; then 'one, zero, zero'; -'one, zero, one'; an such like. These are equivalent to Decimal 0,1,2,3,4,5. How can this relate with computers? That's next.
In our computer we've transistor switches, as described above. For your math case we only looked at, we need 3 buttons. These each represent a Binary Digit, or Bit. To represent a Decimal 1, these switches would be OFF,OFF,ON or 001. To get a Decimal 5 we would have ON,OFF,ON, or 101. By expansion you can view that with 4 changes we could visit 1111 or 15 Decimal.
Still another point to note is that each binary digit, or bit, has a value. Just like in Decimal we have units, tens, hundreds, an such like. in Binary the values are 1,2,4,8,16,32,64,128 and so on. And so forth. The binary code 1111 stated earlier is ergo 1+2+4+8=15. If you wished to work out what binary 100101100 was in decimal, you can add up the individual values. In reality people that work on the essential products need to find out 'device signal'! In their mind 1111 will be F in Hexadecimal or 1-7 in octal.
That probably seems an extremely long-winded approach to work out figures, until you understand that these 'changes' can operate at nanosecond pace or 1,000,000,000 times per 2nd, big measurements become possible.
Thats probably enough to consume in a single go. The next time we shall have a look at how a computer adds and multiplies..
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