# VirtualMV/Data

## Data in a digital age

Information Revolution: http://www.youtube.com/watch?v=-4CV05HyAbM (Wesch, 2007)[1] {5min 29sec}

## Storage comparisons

... and the speedo has been binary adjusted 1km equals 1024 meters !!

Bit (b) = 0/1 Byte (B) = 8 bits (used to represent one character (e.g. A, B, C, etc...)

1 Kilo byte (KB) = 1024 bytes (this is why hard disks have a different size when you look up their technical data)

### Some terms

• 1 024 Bytes = 1 Kilobyte (2^10 / 10^3)
• 1 024 Kilobytes = 1 Megabyte (2^20 / 10^6) = 1 048 576 Bytes
• 1 024 Megabytes = 1 Gigabyte (2^30 / 10^9) = 1 073 741 824 Bytes
• 1 024 Gigabytes = 1 Terabyte (2^40 / 10^12)
• 1 024 Terabytes = 1 Petabyte (2^50 / 10^15)
• 1 024 Petabytes = 1 Exabyte (2^60 / 10^18)
• 1 024 Exabytes = 1 Zettabyte (2^70 / 10^21)
• 1 024 Zetabytes = 1 Yottabyte (2^80 / 10^24)

(In 1993 Morgan Burke proposed adding graucho (2^90 ) and harpo (2^100 ). This has not been formally accepted.)

-) I hear there's a band called 1023MB they haven't had any gigs yet !!

## Text represented electronically

Consider a light switch. The light can represent two states: ON and OFF. In computer terms the light switch would be called a BIT.

Now think of two switches attached to lights. We can now represent 4 states: off-off (00), off-on (01), on-off (1-0) and on-on (1-1). If we assign letter to the four states 00=A, 01=B, 10=C and 11=D we could send a message to a distant place (so long as they could see our lights. So if we sent 10 00 11, the message would read CAD.

Looking at the keyboard, there are lots of letters to display (a-z, A-Z, 0-9, and the special ones like !@#$). Development of a code suitable for electronic transmission was started around 1960, and was called the American Standard Code for Information Interchange (ASCII). ASCII uses 8 bits to represent characters (Glyphs), and this is known as a BYTE. (ASCII,2010)[2])For example:  Binary Glyph 0010 0100$ 0011 0000 0 0100 0001 A

For a complete list go to the Wikipedia ASCII Page [2]

### How many bytes on an A4 page?

Text characters on an A4 page

Assume;

• Non-proportional font, of about 10 pitch;
• Paper width = 80 characters
• Paper height = 66 lines
• Margins of;
• top = 10 lines,
• bottom = 6 lines
• sides = 10 characters
• Calculation
• 60 characters x 50 lines
• = 3,000 characters
• = (approx. 3 Kilobytes)

### How may bytes in a phone book?

For Napier/Hastings (population: approx. 100,000)

• Characters per line 40
• Lines per page x 100
• Number of columns x 5
• Number of pages x 190

### How does a computer handle those characters found in other languages??

Just to complete the discussion, How does a computer handle those characters found in other languages? UNICODE was developed from around 1987, and allows for several coding schemes the most common being the Unicode Transformation Format-8 (UTF-8). UTF-8 uses from 1 to 4 bytes, with the first byte for ASCII (to remain compatible), and can represent most modern (e.g. Hebrew, Chinese, Russian), and ancient languages.(Unicode, 2010)[3]

## And some examples

Inflation (approx 10 T\$)?

## Coding Systems

### Example: Bus seat numbering

2013 Seat numbering in a tour bus. Photo by Inge M.

### References

1. Wesch, M. (2007) Information Revolution, YouTube. Retrieved February 12, 2009 from http://www.youtube.com/watch?v=-4CV05HyAbM
2. ASCII. (2010, February 9). In Wikipedia, The Free Encyclopedia. Retrieved 08:28, February 25, 2010, from http://en.wikipedia.org/w/index.php?title=ASCII&oldid=34290988
3. Unicode. (2010, February 23). In Wikipedia, The Free Encyclopedia. Retrieved 09:05, February 25, 2010, from http://en.wikipedia.org/w/index.php?title=Unicode&oldid=345809172
4. Vodaphone (2010). Internet on your mobile. Retrieved February 21, 2010 from http://www.vodafone.co.nz/mobile-data/mobile-web.jsp?