IT in the context of law
Week 1:
Lecture Readings:
Hardware: the solid, visible part of computing
What’s in a Computer?
Two viewpoints:
1. The logical or functional organisation—what the pieces are, what they do and how
they are connected
2. The physical structure—what the pieces look like and how they are built.
Network effect: the more other people use something, the more useful it will be for you,
roughly in proportion to how many others there are.
Logical Construction:
- processor (the CPU):
The CPU does arithmetic, moves data around, and controls the operation of the other
components.
- primary memory (RAM):
Stores information that is in active use by the processor and other parts of the computer.
Most RAM is volatile, that is, its contents disappear if the power is turned off, and all this
currently active information is lost.
- secondary storage (a disk)
Secondary storage holds information even when the power is turned off.
a. The magnetic disk, usually called the hard disk or hard drive,
b. flash memory, often called solid state disk.
- wires (bus)
Physical Construction:
Transistor: a switch, a device that can turn a current on or off under the control of a voltage.
>Logic gates are created on integrated circuits or ICs, often called chips or microchips.
Moore’s Law:
Every 18 months or so the number of devices that can be put on an integrated circuit of a
given size approximately doubles.
Bits, Bytes, and Representation of Information:
“Analog”: values that change smoothly as something else changes. (eg speedometer or clock
needle)
,“Digital: a small change in something results either in no change or in a sudden change in
something else, from one of its discrete values to another.
>digital data is easy for computers to work with. It can be stored, transported, and
processed
in many ways regardless of its original source.
Digital system advantage over analog: they are much more easily extended.
Analog system advantage: they all stood the test of time in a way that digital forms may not.
Analog-Digital Conversion:
- Images: colour- RGB (red, green, blue)
- Sound: digital representation of waveform (eg. CD)
Digital systems represent information of all types as numeric values, with a binary system-
numbers in base two.
Bit=a digit that takes on either the value 0 or the value 1, with no other possibilities.
Byte=a group of eight bits
Inside the CPU:
>most important component of a computer
Branch instructions:
- GOTO instruction/“branch”/ “jump”: tells the CPU to take its next instruction not
from the next one in sequence but from the location specified in the GOTO
instruction itself.
- IF: Because there’s no way to stop this repeated sequence of instructions, or loop,
from continuing indefinitely, ‘if+something’ is used to lead to a conclusion (eg. ‘IF
ZERO’: if zero appears then the system stops)
CPU:
Modern computers use a small number of high-speed memories called caches between the
CPU and the RAM to hold recently used instructions and data. Accessing information that
can be found in a cache is faster than waiting for it to come from RAM.
Caching: cache is a small, very fast memory that is used to store recently used information
to avoid accessing the RAM.
Other types of computers:
, ● Supercomputers: tend to have a large number of processors and a lot of memory,
and the processors themselves may have instructions that process certain kinds of
data much faster
● Graphics Processing Unit (GPU): specialised processor that performs certain
graphics computations much faster than a general-purpose CPU.
● Distributed computing: computers that are more independent—they don’t share
memory
Turing machine:
Created by Alan Turing in WWII, to decipher German messages.
Turing test:
Used to assess whether a computer was displaying human intelligence.
Conversation between a human with an interrogator and a computer with an interrogator.
Turing claimed that if the two could not be reliably distinguished, the computer was
displaying intelligent behaviour.
Example of reverse Turing test (attempts to distinguish between human and computer by
using the fact that people are generally better at identifying the visual patterns than
computers are):
CAPTCHAs: the distorted patterns of letters that are widely used to try to ensure that the
user of a web site is a human, not a program.
Lecture 1:
Information technology:
>Society and social norms change with its technological advances, of which information
processing is fundamental
>Language: embody ideas/concepts
>Writing
>Printing press: revolutionary change
>Telecommunications (eg. telegraph, telephone)
Francis Bacon-New Atlantis:
- A better society through scientific and technological development
- Increasing interest in worldly affairs; materialist worldview.
- Rise of industrialisation drives the need for tools to manage the increasing
complexity of tasks and information.
>We develop ways to allow for the capture and storage of data
>This data can provide (varying degrees of) insights and predictions about any phenomena
, >Our ‘information technology’ allows for the management of complexity
Drawbacks:
- Unforeseen social and behavioural developments (harder to create laws if you do
not know how technology will be used)
- Critical dependence on the systems for basic functions
- Power imbalances in society (who owns the data?)
Establishing control:
- Societies establish rules for controlling behaviour
- The law provides boundaries for actions, procedures for transactions, and practical
resolutions to conflict.
- Law relies on consistency to ensure stability. How does this work with
fast-developing technology?
Information technology:
“The branch of technology concerned with the dissemination, processing, and storage of
information, especially by means of computers.”
What is a computer?
- Computes (processes)information
- Stores information
- Communicates information
Turing Machine:
>Alan Turing devised a theoretical machine which could be used to solve problems
>The machine executes a sequence of discrete steps and assumes only one of a determines
finite states at any moment
>If the problem has an outcome, the machine will output an answer
How do we represent information in a computer?
- Computers tend to represent data internally as base-2, also called binary.
- A bit (“binary digit”) is the most basic unit of information.
- Each digit contains only one bit of information, either 1 or 0.
How much information can we encode?
1 bit: 2 digits
2 bits: 4 digits etc.
>For n bits we can encode 2n bits of information
