Everything you wanted to know about computers but never dare ask. Part 1

1. Agenda
SESSION 1
Introduction
Nothing new under the Sun
Computer Components
Computer Types
The Secret?
But why do they all seem so different?
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2. Introduction
tell you “Click X to do Y“
teach you step-by-step how to send
an email/Skype your son/etc
advise you on the best computer
etc…
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Why Not?
Because nobody can remember that stuff
It will be different next week
Everyone’s needs are different
“I can’t be bothered with all this medical
stuff, show me how to do brain surgery”
These Sessions Will Not:

3. Introduction
Show you HOW to be comfortable with
new technologies
Show you WHY the new ways may be
advantageous for you
Help overcome the fear
Accept change
By
Explaining the jargon
Introducing the concepts
Getting you to think “Oh, this is like…”
Showing you can’t “break” a computer…
usually
These Sessions Will Try to:
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4. There’s Nothing New
Under The Sun
How have computers
changed what we do?
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5. There’s Nothing New
Under The Sun
How have computers changed
what we do?
They HAVEN’T changed WHAT
They HAVE changed HOW
So you don’t HAVE to embrace
them… it’s your choice.
Don’t be pressured.
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6. What Do We Do With
Computers
We eat
We work
We play games
We read
We write letters
We shop
We listen to music
We go to the theatre
We entertained ourselves at
home
We watch TV and films
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7. What Did We Do Before
Computers
We ate
We went to work
We played games
We read
We wrote letters
We shopped
We listened to music
We went to the theatre and films
We entertained ourselves at home
We watched TV and videos
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8. Before The Telephone
We ate
We went to work
We played games
We read
We wrote letters
We shopped
We listened to music
We went to the theatre
We watched films at the cinema
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9. Before Trains
We ate
We went to work
We played games
We read
We wrote letters
We shopped
We listened to music
We went to the theatre
We sang around the piano
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10. The Secret of
Computers?
All computers work
the same way
They follow recipes/patterns/
instructions…
… and it is:
Like cooking a meal
Like playing a piece of music
Like knitting a scarf
Like building IKEA furniture
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11. Cooks work the same
way! They follow a recipe
Initially recipes are in cookery
books on a shelf
The book with the recipe is taken
from the shelf
The cook opens the book at the
right page, reads the recipe from
the book and follows it
The cook writes any changes to
recipe into the book
The book with the modified recipe
is put back on the shelf
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12. Computers work the same
way! They follow instructions
Initially all data (apps and
information) is on storage devices
Data is loaded into memory
Processor reads app from memory
and follows instructions, using
data when required
Processor writes data into memory
New data is saved to storage
device
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13. Cooking vs Computers
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Cooking Computers
Initially recipes are in cookery
books on a shelf
Initially all data is on storage
devices
The book with the recipe is
taken from the shelf and put on
work surface
Data is loaded into memory and
displayed on desktop
The cook opens the book at the
right page, reads the recipe from
the book and follows it
Processor reads app from
memory and follows instructions,
using data when required
The cook writes any changes to
recipe into the book
Processor writes data into
memory
The book with the modified
recipe is put back on the shelf
New data is saved to storage
device

14. An App or Program
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A set of instructions to
achieve a result
Like a recipe in cooking
Or a pattern in knitting
Or a blueprint in building
Or a score in music
A set of Apps is like a set of
kitchen tools or musical
instruments… probably more
than one can do the job but
one is perfect.

15. Computers vs Eating
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Computers Eating
Mainframe Restaurant
Midframe Snack Bar
Server Takeaway
Workstation Designer Kitchen
Desktop Normal Kitchen
Laptop Camping Stove
Smartphone
All of the above but the plates are
tiny!
Tablet A BIG Smartphone
Personal Computers

16. The First Computers
Abacus
Slide Rule
Sextant
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Analog and special purpose

17. The First “Computers”
A job - a human who performed
calculations or computations
(1613) e.g. log tables
Babbage’s Difference Engine
(1822)
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18. First Programable
Computers
Jacquard Loom
Punched cards
Pianola
Punched paper roll
Colossus
Pinboard and paper tape
at Bletchley Park used by Alan
Turing and the code breakers
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19. Computer Components
MEMORY
•Fast, expensive, forgets when powered off
STORAGE
•Slow, cheap, remembers when powered off
PROCESSOR
•Does as it is told to by the app
DISPLAY
•Displays what the app wants
KEYBOARD
•Relays your wishes to the apps
POINTER
•Identifies the bit you are interested in
•APP ( OR PROGRAM)
•The set of instructions to perform a task - the recipe or pattern
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20. Memory
Fast, expensive and needs
power
Usually called Random
Access Memory (RAM)
Its the processor’s
scratchpad and data source
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IBM 360/65 1KB
Modern Laptop 8GB
x 8,000,000
=

21. Storage
The generic name for anything that
holds data after being powered off.
Wire recorder
Tape recorder
Personal computers originally had
a “floppy”
Usually seen as a hard drive
Can also be tape
Or CDROM/DVD
Or “CLOUD”
Or … TBD
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Floppies
x 1,000,000
=
1.4MB
1TB Hard
Drive

22. The Processor - the brain
Reads the program and
data from memory
Executes the instructions
Stores the results in
memory
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1980
2014

23. Some Jargon - Units
Bytes
1 Character
Kilobytes
1000 bytes
Megabytes
1000 kilobytes
Gigabytes
1000 megabytes
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24. 24
A Kilobyte(KB)- An average email text is about 2
kilobytes
A 5-page paper might be 100 kilobytes
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1000 Bytes = 1 Kilobyte1Byte
My first thought was how did the Apollo
computer compare to the iPhone? It turns
out that's a really tough comparison to
make. The iPhone is so advanced
compared to the computer used in Apollo's
guidance system that it's hard to believe
they both came from the same planet -- at
roughly the same period in time when
viewed in contrast to man's time line on
Earth. To really make a comparison that
makes much sense it's much easier to look
at the home computers of the late 1970's
and early 1980's.
Take Intel's venerable 8086 for example --
you might know it better as "x86". Released
in 1979, just a decade after Apollo 11's trip
to the Moon, the 8086's cousin, the 8088,
formed the basis for the IBM PC we all
know and love. When the IBM PC "XT" was
released in 1981, the lowest end
configuration had 8 times more memory
than Apollo's Guidance Computer -- 16k,
vs the Apollo's 2k. The read-only storage of
the AGC was 32k,
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25. 1000 KiloBytes = 1 Megabyte1KB
A Megabyte (MB) - audio is about 1 megabyte per
minute
A high quality digital picture is about 2-5 megabytes
Apollo 11 Guidance Computer 2KB
First IBM PC 16KB
"640K ought to be enough for anybody.”
Bill Gates, 1981 (denied)

26. A Gigabyte - High definition video is
about 10 gigabytes a minute
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1000 Megabytes = 1 Gigabyte1MB
BBC Micro 32MB

27. A Terrabyte (TB)
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1000 Gigabytes = 1 Terrabyte1GB
Dell Laptop 1GB RAM
Biggest XP Laptop 4GB RAM
1 minute HD Movie 10GB

28. A Mainframe
As big as a house
Lots of big boxes
££££££££ in price
Used for complex calculations
Cards In and Out (I/O)
Disk and Tape Storage
Used by many people at the same time
using terminals or text-only Visual
Display Units (VDU)
IBM introduced a standard architecture -
and took over the world for 3 decades.
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IBM 360/65
IBM 3279 VDU

29. A Mini
Generic name for a
number of expensive but
limited use computers
that were smaller than a
mainframe
e.g. DEC PDP, English
Electric 4Pi, ….
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30. A Server
Faster, more storage, more memory
Lots in one room
Used to save and process all types of data
Processor and Storage
No keyboard or display
Network connected
Replaced Mainframes
Professionally managed
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31. A Workstation
For complex tasks
Faster, more storage, more
memory
Used by graphics designers,
video editors, special effect
engineers, scientists
Used to save and process lots
of complex data
High resolution screens
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32. A Desktop
The first Personal “Home” computer
A simplified workstation
Designed by “Mainframe thinking”
It looked like a VDU
Several Components
Screen
Keyboard
Box of bits - the system unit
IBM introduced a standard architecture
But a mainframe-based text user interface
TRS-80
Apple II
IBM PC
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33. A Laptop
All components in one box
Portable
More expensive than a
desktop
More convenient than a
desktop
Quieter than a desktop
BUT… all the same type of
components
Apple Macbook
Dell
Latitude
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34. Small is good
Portable laptops changed the
way people used computers
People were not tied to their
homes or offices
People really had a Personal
computer
This was a major new revenue
source for manufacturers
If small is good then smaller
must be better
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35. A Netbook or Notebook
Just a small laptop
Smaller keyboard
Smaller screen
No CD drive
Less expensive than laptop
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36. A Chromebook
A new concept from Google
All the normal components
EXCEPT for storage
All data is stored online - at
Google in their CLOUD
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37. Tablets
Just the same inside as Mainframes, Servers, Desktops,
Laptops and Notebooks - but repackaged
BUT a different operating system and user interface
AND memory that remembers AFTER power is
removed
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38. Questions?
About today
Still unanswered
Anything else
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39. Follow the course on the
web at wingvillagehall.club
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