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M150: Data, Computing and Information Data and information: an introduction 1 1- Introduction Aims of this unit: Using case studies that relate the use of computers to finding, storing, processing and disseminating data and information; Describing various instances of computer use to see how computers can work with data to produce information; Introducing you to what a browser is, and how to use it Demonstrating how to use a search engine to find information more effectively. 2 1- Introduction Most people experience computers not only as a remote machines producing bills or directing space flight, but also its used as medium that combines graphics, video, sound and text to impart information and a means of enabling us to shop on the internet, and also to controlling everything. Example of cards holding data you may need on daily basis: Driving license Credit cards Sports club membership card Your ID 3 2- Daily life and computers We are use Computers in our daily lives, but many of them are invisible to us Individual activities: Radio- alarm Cooker Car (conrol the steering, manage the engine,control the braking system , navigation system) Write material using computer, send and receive emails Bank (automated teller machine or ATM) Mobile telephone Supermarkets (order items) Police speed camera 2- Daily life and computers Organization activities Loyalty cards( cards that offer a customer some form of incentive, such as a future discount or gift, to continue buying from that firm) The example of loyalty cards was used to demonstrate how the data associated with such cards could be used to derive information that could be put to subtle use 2- Daily life and computers Two words are used in connection with computers: Data refers to discrete items, such as the price of an item, or the type of product. Information involves linking together two or more items of data to provide an item of knowledge (Information can be thought of as the answer to a question 3- Sensing data and turning it into something usable Transform sensation into appropriate form If you touch a surface, one of the things you will sense is its temperature We have developed words like ‘hot’, ‘cold’, ‘warm’, and ‘cool’ Such words allow us to link one sensation (touch) to another (vision) we have developed more objective measures of hot and cold, such as the length of a column of mercury in a thermometer. What we perceive with our senses we call the most primitive form of data: perceptual data. 7 3- Sensing data and turning it into something usable Arts marks meant to the people who made them A sign or symbol is a way of representing data. A sign (or symbol) can be defined as something that conveys some information by means other than direct representation. Beeping sound (audible signs) Road traffic (visual sign) Flags Legends on maps Braille (tactile sign): which is intended to be read by those with a visual impairment using the tips of the fingers Words are also a signs (name is a sign) 8 3- Sensing data and turning it into something usable Data and information: Human beings turn data into information through a process of creating signs to represent the data; agreeing on what the signs symbolize; linking these signs in a variety of ways to create information; communicating that information to other people. Example: Recipe for making a cake 9 3- Sensing data and turning it into something usable What has any of this to do with computers Computers can mimic our senses and gather data we have no way of dealing with directly (Example: photographs from space) Modern computer systems with their incredible capabilities enable us to sense, store, process, transmit and display data in ways that were previously unimaginable The information that computers produce can be used to control devices like mechanical or hydraulic machinery. (which can be dangerous for humans to operate) 10 3- Sensing data and turning it into something usable Computers have vast memories. Once such data is stored, we do not need to remember it: rather we can concentrate on remembering what it describes and where it can be found. A computer system is the combination of: The computer (with its processor and storage) Other equipment such as a scanner or printer The software programs that make it all work 4- Computers as tools for finding Computers can be used to find information. (World Wide Web “WWW”) Also computers can be used to find things in the sense of locating them geographically (maps, navigation system) The role of the computer is to transform data into information The presentation of information needs to be fit-for- purpose (the form of presentation depends on the requirements of the user or the situation in which the information is needed) 4- Computers as tools for finding Maps (Maps Layers): Maps use latitude and longitude to form a two dimensional grid Contour lines give an idea of the topography of the area (altitude) Features such as rivers, roads, buildings and boundaries; The names of towns, roads, hills, rivers and other notable features of the landscape. 13 4- Computers as tools for finding Geographical data Stored in databases (collections of data) Leave out some layers for a particular purpose Global positioning system (GPS) Is used to tell you where you are. (aircraft, ships, cars) Examples of applications for GPS are: Navigation Surveying and establishing the shortest distance between two points Seeing how large areas of the earth’s surface move relative to each other What happens when a map is wholly inappropriate (navigating in the dark, smoke or fog, or if the user has a visual impairment) give audible directions 14 4- Computers as tools for finding Finding information: the web A browser, like Internet Explorer, is used to access web Different between web and internet The internet refers to the physical interconnection of large numbers of smaller data communications networks to form a huge, publicly accessible ‘network of networks’. Thus the internet carries email, hosts chat rooms, enables the transfer of files, and is the physical basis for supporting the World Wide Web. The web is the collection of linked data stored on the internet which is accessed using a browser Search engines The computer application that facilitates finding things on the web Single box waiting the keyword Serves a similar function to an index in a book Example: Google, Yahoo, Lycos, … 15 4- Computers as tools for finding Finding information: the web The process: 1. The keywords are transmitted over the internet to a web server that contains an index to websites which is associated with a series of keywords that can be found in the site’s title, address or contents. The index keywords and the user’s requested keywords are compared by the server. 2. The web server then retrieves references to those websites that contain the right keywords and sends details of each reference back to the user’s browser. 3. The browser then displays the references for the user. 17 4- Computers as tools for finding Finding information: the web Using the web more effectively: the gateways A gateway on the web is a website intended to direct users to other preselected websites containing information on a particular topic. Using a search engine more effectively One of the problems with finding information on the web is that there is so much, and not all of it is relevant to what you want. You can solve the problem by Looking for phrases rather than individual words Use a selectable topic like Advanced Search or Search Tips. Choose keywords carefully Computer program is a set of instructions that tell the computer what to do 18 5- Computers as tools for working with data The computer and its programs are tools for working with data. Two studies provide an interesting contrast between: Simple data( consisting only four elements) in large and complex structures( genes and chromosomes) ,which require large and complex programs to handle them DNA Complex data (graphical representation of a sense) which a complex program helps a non-expert to handle in some interesting, creative, flexible ways Arts 19 5- Computers as tools for working with data Computers as tools for working with data DNA: What is DNA? DNA (deoxyribonucleic acid) is frequently in the news for many reasons such as it can be used in crime detection, in medicine to detect the possibility that diseases having a genetic origin may occur in an individual, and to identify victims of disasters It consists of pairs of chemical bases called adenine (A), cytosine (C), guanine (G) and thymine (T). A nucleotide is a base pair plus its attached ‘structural’ molecules (i.e. the sides of the ladder). A complete DNA strand constitutes a chromosome (a human being has 46 of these combined into 23 pairs). 20 5- Computers as tools for working with data DNA A DNA strand, bases, nucleotides, genes, and a chromosome (a) A small section of a DNA strand as though it were untwisted. Each box represents a base (A, C, G or T). Each pair of bases forms one nucleotide. Several nucleotides make up a gene (shown by brackets) (b) How the strand of DNA in (a) is twisted into the famous double helix (c) A chromosome formed from one DNA strand 21 5- Computers as tools for working with data Art and the computers Artists use their skill to transform natural objects, materials or signs (paint, clay, their own body or voice, the sounds of musical instrument, words) into something else. Photograph Painting Infinite color spectrum Transforming the natural to the designed The computers, as an artist’s tool, can produce effects that would be difficult using traditional media. (The flexibility of a computer system, allow you to make may copies of something) 22 6- Controlling things; selling things Computers can collect, process, store and distribute information (as you mention previously). They can also control machines and selling on the web. Controlling things Examples: automatic washing machine or microwave that contains microcomputer The user interface Displaying the choices Displaying indications Choosing programs and parameters Ensuring safety Controlling the machine Actuators Sensors 23 6- Controlling things; selling things Selling on the web The web is a medium for selling everything from books to clothes, beauty products, investment advice to travel services Three main categories of company in Web based selling: Existing catalogue sales companies which have put their catalogues online to allow customers to buy using the web Existing companies whose products are largely information and which have used the web as a means of providing a personalized service or one with a very quick response; (Professional Journals) Companies which have started from scratch using the web as their only sales medium. (Online bookseller (Amazon)) The most successful financially have been those in the second category 24 6- Controlling things; selling things Selling on the web Browse through the details of the goods for sale Search for a particular product Check the availability of goods Read and review the comment of other purchasers Register to receive newsletters But product using credit or debit cards See what items are most popular 25 6- Controlling things; selling things Database servers is a computer that responds to requests from other computers. Its task is to find and extract data from a database. Distributed system means that separate computers exchange data and information across a network (in this case the internet) to produce results for a user. The parts of distributed system are: The web server The database server 26 6- Controlling things; selling things Security: are your credit card details safe? The internet is a remarkably open medium You can be reasonably confident of buying from a website if it displays one of two things: 1. The address shown in the bar should start with ‘https’ instead of ‘http’. The letter ‘s’ means you are connected to a secure web server 2. An icon representing a small key is present. 27