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Unit 1 Information, Systems and Applications Data, Information, Knowledge and Processing   

Data made up of alphanumeric characters, random without meaning Information = Data + Structure + Context + Meaning Knowledge – application and use of the information

Representation Methods     

Text (including writing) Graphics (including pictures) Sound (including voice) Moving Pictures (animation or video) LED (sequence of lights)

Data Types     

Boolean (true/false, e.g. Y/N M/F T/F) Real (numbers with decimals e.g. 2.569) Integer (whole numbers e.g. 18) Date/Time {dates/times 12/3/09} String (array of letters e.g. Michael)

Sources of Data Direct and Indirect  

Direct – YOU have collected the data Indirect – someone else has collected it [purpose same or different e.g. loyalty cards points & analysing buying trends)

Static and Dynamic Data  

Static cannot be changed (e.g. CD ROM) Dynamic can be updated (e.g. web page)

Quality of Information      

Accuracy (no good if inaccurate – different levels of accuracy) Relevance (is it suitable to the need?) Age (past its usefulness?) Completeness (are necessary facts present?) Presentation (is it useable?) Level of detail (is it suitable to the need?)


Encoding Data 

Validation & Verification – Neither can ensure the accuracy of

the entered data e.g. Ms Fitzgerald’s age is 21 – valid (& believable of course) but not accurate – I’m 25 really.

Validation ensures data is REASONABLE, COMPLETE, SENSIBLE AND WITHIN ACCEPTED BOUNDARIES, achieved by:     

Range (e.g. 0-15, 16-18, 19-80) Type (e.g. text, number, Boolean) Presence check (must be completed e.g. Gender) Length check (e.g. Must not exceed 25 characters) Picture check / FORMAT check (e.g. DD/MM/YY)

Verification ensures the source and object data are the same. Achieved by: 

Proofreading (human)

Computer verification (keying in twice to make sure the same data is entered, such as when you change your password).

Danger of ‘opinions’ being coded, likes/dislikes. EG The service is a) Excellent, b) Good, c) OK, d) Poor Are the classifications/options correct?

Backup and Archive 

Back up is making a COPY OF THE DATA

Archive is REMOVING THE DATA FROM DIRECT ACCESS, storing it in case it is needed


Cost of Information Hardware – specialist equipment e.g. Scanner Camera Graphics tablet Microphone Etc Software – used for specific tasks e.g. DTP Graphics Spreadsheet Stock control Etc. Personnel (staff) New employees Training of individuals Consumables (things used on a daily basis) Electricity Ink Paper

Generic ICT System Input – external data put into the system {using various methods} Process – manipulating the data {sorting, searching, calculating} Output – data being passed outside the system Feedback – output influencing the input Input

Process

Feedback

Output


Software and Hardware Components of an Information System Difference between hardware & software Hardware – physical equipment that you can touch (e.g. keyboard, monitor, processor, printer) Software – programs used on the computer to carry out tasks (e.g. word processor, spreadsheet, operating system, EPOS system)

Lack of Standardisation Incompatibility – e.g. old graphics card won’t work in new computer – COST implications, nuisance value, loss of time.

Input, Output and Storage Devices Input – Getting DATA INTO a system; e.g. Keyboard, mouse, graphics tablet, scanner, digitiser, microphone

Output – Getting INFORMATION OUT of a system; e.g. Printer, plotter, speaker, monitor

Storage – holding data within the system e.g. Internal hard disk drive, external hard disk drive, CD, CDR, CDRW, DVD, DVDR, DVDRW, Memory Stick, floppy disk, tape

Specialist Hardware Devices - Puff suck switch, mouth stick, foot mouse, eye-typer, Braille printer, Braille keyboard

Specialist Software – Text to speech, magnifier, predictive text, sticky keys


Different Types of Software Operating system – core software allows the computer’s hardware parts to act as a computer

Utilities – additional programs to make the use of the computer easier (housekeeping – delete files, rename files, put files in folders etc)

User Interface – Method by which the user communicates with the computer.

Applications software – software programs written to do particular

tasks, usually replacing manual methods (e.g. word processor, spreadsheet, database)


Characteristics of Different User Interfaces Command Line – user types commands at prompt, can use switches, low memory costs but specialist knowledge required.

Forms – structured areas for responses, validated and logical:


Menus – drop down, pop up and context sensitive, can be part of WIMP

Natural Language: written or spoken everyday language, computer translates into commands needed to operate.


Characteristics of Standard Applications Software and Application Areas Types of software used for basic tasks: Word processor – letters, memos, reports, books DTP (Desk Top Publisher) – brochures, posters, business cards Spreadsheet – graphs, charts, forecasting, accounts, modelling Database – storing, searching, sorting records Web page authoring – creating web pages Presentation – electronic slide shows, acetates (printed slides)

Application Areas: 

School administration & Teaching systems (student details, contact details, attendance, punctuality, marks etc)

Stock control (item number, description, cost, price, number in stock, reorder level, supplier, delivery time etc)

Booking systems (venue, ticket/seat number, date etc)

Online training systems (tasks, animation, examples, video, sound etc)

Timetabling and route finding systems (start & finish points, alternative routes, traffic warnings, speed camera warnings etc)

Customer records systems (customer number, name, address, invoices, credit notes, statements etc)

Online banking systems (account number, name, transactions [money in/out], balance, overdraft limit etc)


Wizards, Styles, Templates, Macros 

Wizards – step by step guides to produce a document, form, function (eg vlookup) or webpage

Styles – master documents, layout, colour scheme, fonts etc

Templates – Pre-defined layouts for font, page layout, graphics etc.

Macros – Set of stored commands that can be recorded by the user. Activated by key combinations or icons. E.g. could be used to put a header onto a document.

Design Considerations for Tailored Data Entry Screens       

Consistent layout (house style) Standard font size, font colour Complementary screen background and foreground colours Clear error messages Good flow of information Validation on certain fields to ensure accuracy/reasonableness Good on screen help facilities

Customisation of Standard/Generic Applications Software Buttons, forms, form controls, macros can be created to make the software easier to use.

Think about examples from your

structured tasks – how you made your spreadsheet and database easy for a user to operate. Advantages – software can be ‘tailored’ to meet specific needs of an organisation. Can speed up data entry and minimise risk of errors in data. Disadvantages – staff need to be trained to ‘tailor’ software. Training takes up time and money & person might leave. Errors might occur that people are not aware of.


House Style Use of colour scheme, logo and fonts. Clients / customers can easily ‘recognise’ company; consistency across all documents presents professional appearance. Master documents, master slides, style sheets and templates allow the house style to be adhered to.

Letter heads, business cards, invoices, credit notes, statements, web site / pages, decoration of vehicles, premises, advertisements, products.


Transferring Files Between Application Programs To transfer a file from one program to another. Think of A (e.g. spreadsheet) as the source program and B (e.g. word processor) as the destination program. Open the file in program A SAVE AS common format (eg CSV) Open the file in program B


Unit 1 The Role and Impact of ICT Data Protection Act (1998)   

Aim – to protect individuals from organisations. Allows individuals to have ACCESS to information stored about them. Inaccurate information should be changed/corrected

Eight Principles of DP Act say that information should be: 1. 2. 3. 4. 5. 6. 7. 8.

Fairly and lawfully processed Processed for limited purposes Adequate, relevant and not excessive Accurate and up to date Not kept for longer than is necessary Processed in line with your rights Secure Not transferred to other countries without adequate protection

Exemptions to the Act include national security, crime and taxation, health, education and social work, domestic purposes (e.g. your own private data such as friends’ names and telephone numbers).

Data Subject – the person the data is held about Data Controller – person in organisation responsible for data processing

Computer Misuse Act (1990) To protect companies from HACKERS. Makes the following four points illegal:    

Unauthorised access to a computer's software or data (hacking) - including the illegal copying of programs. Unauthorised access to a computer's data for blackmail purposes with the INTENT to commit a crime. Unauthorised access to a computer's data with the intention of altering or deleting it. This includes planting viruses. Copying programs illegally (software piracy).

A conviction may lead to a fine and a 5-year prison sentence.


Copyright, Designs and Patents Act (1988) Protects owners/creators of materials. ICT equipment makes copying of information very easy, CDP Act makes it illegal to, without permission, copy or store:     

Books CDs / DVDs Software Music Artistic Works

Regulation of Investigatory Powers Act (2000) Makes it a criminal offence to monitor communications without lawful authority. Communications include:   

Telephone calls Emails Post etc

Electronic Communications Act (2000) Designed to enhance security of electronic communications. Includes: Register of cryptography providers Digital signatures admissible in law

Freedom of Information Act (2000) Deals with access to official information from any public authority. Person can request information in writing, but request may be refused if information is exempt from FoI Act.

Protecting ICT Systems Physical Methods (eg lock on door, CCTV, position of monitors) Logical Methods (eg firewalls, backup, encryption, biometric security, software patches/updates, antivirus software, anti-spyware software, access rights, education of users, user IDs, passwords, updating/changing passwords – password policies (eg mix of letters & numbers, upper & lower case, must change every 6 weeks).


Networking Computers: Advantages 

 

Shared peripherals (eg printer/scanner) – don’t have to buy one for each pc.

Disadvantages 

Can be costly to set up

If network crashes no-one can use system

Viruses can spread easily

Busy networks can be slow

Data sharing. Access control by network manager.

Program sharing – administrator can monitor use & make sure licence requirements are followed.

Easy communication between users eg. Email /intranet.

Standards Standards mean a common way of doing things, following common rules or PROTOCOLS (eg driving on the right hand side of the road). Without standards organisations cannot communicate easily or share information. Protocols apply to things such as: Emails, printers, passwords, file sharing.


Health and Safety DVT (deep vein thrombosis) – don’t sit too long in one position, move around frequently. RSI (repetitive strain injury) – set workstation up properly, adjustable chair, frequent breaks Ulnar neuritis – elbow pain; avoid leaning elbow, use writs rests Eyestrain – Flicker free monitors, frequent breaks, varied activities Back pain – Adjustable chair, correct posture


Trailing wires Risk of fire Electrocution Unsecured equipment Food & drink in workplace Danger of water



AS ICT Revision Notes