Information Technology Flashcards

Data processing and information

1.1 Data and information

  • Differences between data and information:
    • Data becomes information through context and meaning.
  • Uses of direct and indirect data:
    • Direct data: Collected firsthand (e.g., questionnaires, interviews, data logging, observation).
    • Indirect data: Sourced from third parties (e.g., weather data, census data, electoral register, business data used by others, research from textbooks, journals, and websites).
  • Advantages and disadvantages of direct and indirect data:
    • Direct data: More control over data relevance and accuracy but can be time-consuming and expensive.
    • Indirect data: Readily available and cost-effective but may not perfectly fit specific needs or be entirely accurate.

1.2 Quality of information

  • Factors affecting information quality:
    • Accuracy: Correctness of data.
    • Relevance: Pertinence to the intended use.
    • Age: Timeliness of the data.
    • Level of detail: Appropriateness of granularity.
    • Completeness: Extent to which all necessary data is included.

1.3 Encryption

  • The need for encryption:
    • Protecting sensitive data from unauthorized access.
  • Methods of encryption:
    • Symmetric: Uses a single private key for both encryption and decryption.
    • Asymmetric: Uses a public key for encryption and a private key for decryption.
  • Encryption protocols:
    • Transport Layer Security (TLS)/Secure Socket Layer (SSL): Secures communication over networks, particularly between clients and servers.
    • Internet Protocol Security (IPsec): A suite of protocols for secure IP communications.
  • Uses of encryption:
    • Protection of data at rest and in transit.
    • Systems encryption: Encrypting entire systems or storage devices.
  • Advantages and disadvantages of different protocols and methods of encryption:
    • Symmetric: Faster but key distribution is challenging.
    • Asymmetric: More secure key exchange but slower.
    • TLS/SSL: Widely used for web security but can be vulnerable if not configured correctly.
    • IPsec: Provides robust security but can be complex to set up.

1.4 Checking the accuracy of data

  • Methods and uses of validation:
    • Presence check: Ensures data is entered.
    • Range check: Verifies data falls within specified limits.
    • Type check: Confirms data is of the correct type (e.g., numeric, text).
    • Length check: Ensures data conforms to a defined length.
    • Format check: Validates data matches a specific pattern.
    • Check digit: Uses an algorithm to verify data integrity.
    • Lookup check: Compares data against a known list.
    • Consistency check: Confirms related data is logically consistent.
    • Limit check: Ensures data does not exceed a reasonable threshold.
  • Methods and uses of verification:
    • Visual checking and double data entry: Manual comparison to ensure accuracy.
    • Parity check: Detects errors in data transmission using parity bits.
    • Checksum: Calculates a value to confirm data integrity.
    • Hash total: Sum of non-numeric fields to verify completeness.
    • Control total: Sum of specific fields to ensure accuracy.
  • The difference between validation and verification:
    • Validation: Checks if the data makes sense.
    • Verification: Checks if the data matches the source.
  • The need for both validation and verification:
    • Ensures data is both accurate and sensible.
  • Advantages and disadvantages of validation and verification:
    • Validation: Prevents incorrect data entry but does not guarantee accuracy.
    • Verification: Ensures data matches the source but does not check if the source is correct.

1.5 Data processing

  • Methods and uses of batch processing:
    • Involves processing large volumes of data in a single run (e.g., utility bills, credit card accounts, customer accounts).
    • Uses master and transaction files for updating records in payroll and customer orders.
    • Steps include sequentially updating a master file using a transaction file.
  • Methods and uses of online processing:
    • Processes data immediately as it is entered (e.g., electronic funds transfer, automatic stock control, electronic data interchange, business-to-business transactions, online shopping).
    • Involves real-time updates and immediate feedback.
  • Methods and uses of real-time processing systems:
    • Output affects the input; often involves microprocessor-controlled systems (e.g., greenhouses, central heating systems, air conditioning systems, burglar alarms, traffic control, car park barriers, traffic lights).
    • Wireless sensor and actuator networks (e.g., smart homes, guidance systems, autonomous vehicles).
  • Algorithms for different methods of processing:
    • Sequence of steps to perform batch, online, or real-time processing.
  • Advantages and disadvantages of different methods of data processing:
    • Batch processing: Efficient for large volumes of data but lacks real-time feedback.
    • Online processing: Provides immediate feedback but can be resource-intensive.
    • Real-time processing: Offers immediate control but requires complex systems.

Hardware and software

2.1 Mainframe computers and supercomputers

  • Characteristics of mainframe computers and supercomputers:
    • Longevity: Designed for long-term use.
    • Reliability, Availability, Serviceability (RAS): High uptime and ease of maintenance.
    • Security: Robust security features for protecting sensitive data.
    • Performance metrics: Measured in MIPS (Millions of Instructions Per Second) and FLOPS (Floating-point Operations Per Second).
    • Volume of input, output, and throughput: Capable of handling massive data flows.
    • Fault tolerance: Ability to continue operating despite hardware or software failures.
    • Operating system: Specialized operating systems for resource management.
    • Number of processors: Utilize multiple processors for parallel processing.
    • Heat maintenance: Advanced cooling systems to manage heat generation.
  • Uses of mainframe computers:
    • Census data processing.
    • Transaction processing in banking and finance.
    • Compiling industry statistics.
    • Analyzing consumer statistics.
  • Uses of supercomputers:
    • Weather forecasting and climate research.
    • Quantum mechanics simulations.
  • Advantages and disadvantages of mainframe computers and supercomputers:
    • Mainframes: Reliable and secure but expensive and less flexible.
    • Supercomputers: High-performance but costly and power-intensive.

2.2 System software

  • Types and functions of system software:
    • Compilers: Translate high-level code into machine code.
    • Interpreters: Execute high-level code line by line.
    • Linkers: Combine compiled modules into an executable program.
    • Device drivers: Enable communication between the operating system and hardware devices.
    • Operating systems: Manage hardware and software resources.
    • Utilities: Perform maintenance and support tasks.
  • Uses of system software:
    • Translation of high-level languages using interpreters and cross-compilers to run on different computer systems.
  • Advantages and disadvantages of different types of system software:
    • Compilers: Create optimized code but require recompilation for different platforms.
    • Interpreters: Platform-independent but slower execution.

2.3 Utility software

  • The need for utility software:
    • Anti-virus: Protects against malware.
    • Back-up: Creates copies of data for recovery.
    • Data compression: Reduces file size.
    • Disk defragmentation: Optimizes hard drive performance by rearranging fragmented files.
    • Formatting: Prepares storage devices for use (low-level, partitioning, high-level).
    • File copying: Duplicates files.
    • Deleting files: Removes files from storage.
  • Types of utility software:
    • File management systems: Organize and manage files.
    • Disk management systems: Manage storage devices.
    • Data compression utilities: Compress and decompress files.
  • Uses of the different types of utility software:
    • Maintaining system performance and security.
  • Advantages and disadvantages of different types of utility software:
    • Anti-virus: Essential for security but can impact system performance.
    • Data compression: Saves storage space but requires decompression.
    • Disk defragmentation: Improves performance but can be time-consuming.

2.4 Custom-written software and off-the-shelf software

  • Custom-written software:
    • Developed for specific needs of individuals and organizations.
  • Off-the-shelf software:
    • Ready-made software available for general use.
  • Advantages and disadvantages of different types of custom-written and off-the-shelf software:
    • Custom-written: Tailored to specific needs but can be expensive and time-consuming.
    • Off-the-shelf: Cost-effective and readily available but may not perfectly fit requirements.
    • Degree of testing, level of support, cost, and adaptability are key factors.
  • Proprietary and open-source software:
    • Proprietary: Licensed software with restricted use.
    • Open-source: Software with freely available source code.

2.5 User interfaces

  • Types of user interfaces:
    • Command Line Interface (CLI): Text-based interface.
    • Graphical User Interface (GUI): Visual interface with icons and menus.
    • Dialogue Interface: Interface based on question-answer interactions.
    • Gesture-based Interface: Interface controlled by gestures.
  • Uses of the different types of user interfaces:
    • Vary depending on the application and user needs.
  • Advantages and disadvantages of different types of user interfaces:
    • CLI: Efficient for advanced users but less intuitive.
    • GUI: User-friendly but can be resource-intensive.

Monitoring and control

3.1 Monitoring and measurement technologies

  • Sensors:
    • Light/UV, temperature, pressure, humidity, pH, gas sensors (oxygen, carbon dioxide, carbon monoxide, oxides of nitrogen), sound, infrared, touch sensors, (electro)magnetic field sensors, proximity sensors.
  • Uses of monitoring and measurement technologies:
    • Environmental monitoring: Water pollution, weather stations (temperature, pressure, humidity, light).
    • Monitoring patients in healthcare.
  • Calibration:
    • Importance of calibration for accurate readings.
    • Methods: One-point, two-point, multipoint calibration.
    • Methods of calibrating readings from sensors, for example, temperature sensors.

3.2 Control technologies

  • Sensors and their uses:
    • Touch, temperature, light, moisture, pH, gas, infrared, (electro)magnetic field, ultrasonic, induction loops, sound, and proximity sensors.
    • Examples: touch sensors in fluid level detection, infrared sensors in burglar alarms, proximity sensors in smartphones.
  • Actuators and their uses:
    • Carry out actions/movements: linear, rotary, soft, hydraulic, pneumatic, electric, thermal, magnetic, mechanic.
  • Microprocessor-controlled/computer-controlled technology:
    • Greenhouses, central heating systems, air conditioning systems, burglar alarms, control of traffic/pedestrian flow (including smart motorways), car park barriers, traffic lights, Wireless Sensor and Actuator Networks, smart homes.
  • Advantages and disadvantages of different control technologies:
    • Consider factors such as cost, reliability, and precision.
  • Algorithms and flowcharts:
    • Representing the processing involved in control technologies.

Algorithms and flowcharts

4.1 Algorithms

  • Writing and editing algorithms:
    • Demonstrates decision-making processes, including conditional branching, looping, nested loops, procedures/subroutines.
  • Using pseudocode:
    • INPUT/READ, WRITE/PRINT, FOR…NEXT, FOR…NEXT…STEP, IF…ELSE…ENDIF, WHILE…ENDWHILE, REPEAT…UNTIL, CASE…ENDCASE.
  • Operators:
    • Comparison operators: ,>, <, =.
    • Arithmetic operators: ,+,−,∗,/,+, -, *, /.

4.2 Flowcharts

  • Drawing basic program flowcharts:
    • Solving a given problem and demonstrating decision-making processes.
  • Symbols:
    • Input/output, decision (using comparison operators), terminator (start, stop), process boxes (using arithmetic operators), subroutine, connector, flowline.
  • Editing flowcharts:
    • Demonstrates a decision-making process.
  • Identifying errors:
    • In algorithms/program flowcharts for a given scenario.

eSecurity

5.1 Personal data

  • What personal data is:
    • Information relating to an identifiable individual.
  • Keeping personal data secure and confidential:
    • Why personal data should be kept confidential: To protect privacy and prevent misuse.
    • How personal data can be kept confidential: Removing geotags, anonymizing data, duty of confidence measures.
  • Preventing misuse of personal data:
    • How personal data can be kept secure: Network security measures, firewalls.
    • How personal data can be gathered: Smishing, vishing, phishing, and pharming.
  • Advantages and disadvantages of the different methods of preventing misuse of personal data:
    • Firewalls: Block unauthorized access but can be bypassed.
    • Network security measures: Protect data but can be complex and costly.

5.2 Malware

  • Types of malware:
    • Trojan, worms, spyware, adware, rootkit, malicious bots, ransomware.
  • Uses of malware:
    • Fraud, theft, industrial espionage, sabotage.
  • Consequences of malware for organizations and individuals:
    • Data loss, financial losses, reputational damage.
  • Malware prevention:
    • Software and physical methods.
  • Advantages and disadvantages of the methods of malware prevention:
    • Anti-virus software: Detects and removes malware but may not catch everything.
    • Physical security measures: Prevent physical access but may not protect against network-based attacks.

The digital divide

6.1 The digital divide

  • What the digital divide is:
    • The gap between people and regions with access to modern technology and information, and those without.
  • Causes of the digital divide:
    • Availability of high and low performance computers, wireless connections.
  • Effects of the digital divide:
    • Inequality of access to internet services and technology.
    • Reducing the effects through digital literacy teaching.
  • Groups affected by the digital divide:
    • People in different age groups, cities and rural areas, with differing levels of education and socioeconomic groups, people with accessibility barriers, and people in more and less industrially developed nations.

Expert systems

7.1 Expert systems

  • How expert systems are used:
    • To produce possible solutions for different scenarios.
  • Components:
    • User interface, inference engine, knowledge base (database of facts and rules), explanation system, knowledge base editor.
  • Scenarios:
    • Mineral prospecting, investment analysis, financial planning, insurance planning, car engine fault diagnosis, medical diagnosis, route scheduling for delivery vehicles, plant and animal identification.
  • Concepts:
    • Backward chaining and forward chaining using IF…THEN constructs.
    • Data-driven and goal-driven approaches.
  • Applications:
    • Diagnoses, gaming, artificial intelligence (social media manipulation).
  • Advantages and disadvantages of expert systems:
    • Advantages: Can provide expert knowledge quickly and consistently.
    • Disadvantages: Can be expensive to develop and maintain, lack common sense.

Spreadsheets

8.1 Creating a spreadsheet

  • Creating page/screen structures:
    • Meeting requirements of audience/task specification, including page orientation, size, fit to page, margins, header/footer.
  • Creating/editing spreadsheet structures:
    • Inserting/deleting/hiding/resizing rows and columns, merging cells.
  • Controlling data input:
    • Using validation techniques like drop-down menus.
  • Protecting cells and content:
    • Cells, rows, columns, worksheets, workbooks.
  • Freezing/unfreezing panes and windows.
  • Creating and using formulas:
    • Includes ,addition(+),subtraction(−),multiplication(∗),division(/),indices,addition (+), subtraction (-), multiplication (*), division (/), indices.
  • Referencing:
    • Absolute, relative, and mixed referencing to replicate formulas (named cells, named ranges).
  • Functions:
    • Calculations (SUM, AVERAGE, MIN, MAX, MAXA, INT, ROUND, SUBTOTAL).
    • Counting cells (COUNT, COUNTIF, COUNTIFS, COUNTA, COUNTBLANK).
    • Lookup data (LOOKUP, VLOOKUP, HLOOKUP, XLOOKUP, INDEX, MATCH).
    • Decision-making (IF, IFS, nested IF, AND, OR).
    • Date and time (DATE, TIME, WEEKDAY, DAY, MONTH, YEAR).
    • Extracting values from strings, concatenating strings, testing cell contents.
    • Extracting characters from strings (LEFT, RIGHT, MID, FIND).
    • Conditional formulas (SUMIF, SUMIFS, COUNTIF, COUNTIFS, AVERAGEIF, AVERAGEIFS, MAXIF, MAXIFS, MINIF, MINIFS).
    • Error trapping (ISERROR, IFERROR).
    • Inserting nested functions.
    • Rotating data (TRANSPOSE).
  • Input and error messages.
  • Formatting cells:
    • Date/time, text, numeric, currency, percentage, fractions, text orientation, alignment.
  • Formatting cell emphasis:
    • Size, style, colour, shading, merge, borders, comments, conditional formatting.
  • Appreciation of spreadsheet requirements:
    • Purpose and use for various audiences (age groups, specialisms).

8.2 Testing a spreadsheet

  • Testing spreadsheet structure:
    • Creating and applying a test plan to test functions, validation rules, conditional formatting.
  • Testing data:
    • Need to choose appropriate test data (normal, extreme, abnormal data).

8.3 Using a spreadsheet

  • Extracting data:
    • Searching using text, numeric, date/time, Boolean operators (AND, OR, NOT), ,>,
  • Sorting data:
    • Ascending and descending, applied to single or multiple columns.
  • Summarizing and displaying data:
    • Pivot tables, pivot charts, subtotals, groups.
  • Importing and exporting data:
    • CSV, TXT, PDF, graphs, and charts.

8.4 Graphs and charts

  • Creating appropriate graphs/charts:
    • Appropriate data series (contiguous, non-contiguous data, specified range(s)).
    • Types: Bar chart, pie chart, line graph, comparative bar/line chart, combination chart.
  • Applying chart formatting:
    • Title, legend, segment labels/values/percentages, category axis labels, series labels, field selection buttons, value axis labels, scales, axis scale (max/min), data intervals, add secondary axis, extract pie chart sector.

Modelling

9.1 Modelling and simulations

  • What-if analysis:
    • Predicting results of changing data, modelling different scenarios, goal seek.
    • Uses: Financial forecasting, population growth, climate change, weather systems, queue management, traffic flow, construction.
  • Characteristics of modelling software.
  • Need for computer models.
  • Effectiveness of spreadsheet models.
  • Use of models to create and run simulations:
    • Natural disaster planning, pilot training, learning to drive, nuclear science research.

Database and file concepts

10.1 Creating a database

  • Assigning data types and field sizes:
    • Text, alphanumeric, numeric (integer, decimal), date, time, Boolean.
  • Relationships:
    • One-to-one, one-to-many, many-to-many.
  • Key fields:
    • Primary key, compound key, foreign key, composite key.
  • Referential integrity and its importance.
  • Difference between flat file and relational database:
    • Suitability for certain situations.
  • Creating and using relationships:
    • One-to-one, one-to-many.
  • Entity Relationship Diagram (ERD):
    • Conceptual, logical, physical ERDs.
  • Creating a relational database and setting key fields.
  • Validating and verifying data entry:
    • Using validation rules and testing; verifying data entry.
  • Selecting appropriate query types:
    • Static and dynamic parameters; simple, complex, nested, and summary queries (cross-tab/pivot tables).
  • Performing searches:
    • Simple query on single criterion, complex queries using multiple criteria, static/dynamic parameter queries, nested queries.
    • Using queries to find and remove duplicate records.
    • Using queries to create new tables, append/delete records, and update data.
    • Summarizing data (cross-tab queries).
    • Using text, numeric, date, time, wildcard, Boolean operators (AND,OR,NOTAND, OR, NOT), ,>,
  • Performing calculations:
    • Arithmetic operations, numeric and logical functions, calculated controls/fields.
  • Sorting data:
    • Ascending, descending, sorting on multiple criteria.
  • Designing and creating data entry forms:
    • Appropriate font styles/sizes, spacing, object width/height, white space, radio buttons, drop-down menus, highlighting key fields, form controls, linked subforms.
  • Designing, creating, and editing database reports:
    • Grouped report, controls, calculated controls.
  • Creating a switchboard/menu.
  • Importing data:
    • CSV, TXT.
  • Exporting data:
    • Table, query, report, CSV, TXT, RTF.

10.2 Normalisation to third normal form (3NF)

  • Characteristics of data in:
    • Unnormalised form (UNF), first normal form (1NF), second normal form (2NF), third normal form (3NF).
  • Normalisation of data:
    • Advantages and disadvantages.
  • Normalise a database to:
    • First normal form (1NF), second normal form (2NF), third normal form (3NF).

10.3 Data dictionary

  • Identifying different data types:
    • Text, alphanumeric, numeric (integer, decimal, currency), percentage, date/time, Boolean/logical (yes/no, true/false).
  • Components of a data dictionary.
  • Creating a data dictionary.
    • Selecting appropriate data types for a given set of data and situation.

10.4 File and data management

  • Different file types and their use.
  • Why generic file formats are needed.
  • Proprietary and open-source file formats:
    • Why open-source file formats are needed.
  • Using indexed sequential access.
  • Using direct file access.
  • Using database management systems (DBMS):
    • Hierarchical, network, object-oriented, relational.
  • Features of a management information system (MIS).
  • How a management information system (MIS) can be used by organizations.
  • **Advantages and disadvantages of the different types of database management systems.

Video and audio editing

11.1 Video editing

  • Editing a video clip:
    • Meeting the requirements of its intended application and audience.
    • Setting aspect ratio, trimming, splicing, adding titles/subtitles/captions/credits, ensuring readability, adding fading/pan/zoom effects, transitions.
    • Extracting/resizing/cropping still images, inserting still images.
    • Adding/editing/removing audio, altering clip speed, using filters and colour correction.
    • Exporting in different file formats (MP4, AVI, MOV, WMV), compressing to different resolutions.
  • Effects of different compression methods on video:
    • How they affect video quality.
  • Why typical features in video editing software are used:
    • Trimming, creating text-based slides/credits/captions/subtitles, adding fading effects, extracting/inserting still images, editing audio, exporting, compressing.
  • Advantages and disadvantages of export file formats.

11.2 Audio editing

  • Editing an audio clip:
    • Meeting the requirements of its intended application and audience.
    • Importing new tracks, adding a track, normalising (removing DC offset), trimming, splicing, fading in/out, altering clip speed/pitch, adding/adjusting delay/echo/reverberation.
    • Changing from stereo to mono, applying equalisation/high-low pass filters, noise reduction, overdubbing (voiceover).
    • Compressing to different sample rates, exporting in different file formats (MP3, MP4a, WAV, AAC).
  • How and why typical features in audio editing software are used:
    • Trimming, splicing, fading, normalising, noise reduction, overdubbing, exporting, compressing.
  • Advantages and disadvantages of export file formats.
  • Why file sizes depend on sampling rate and sampling resolution:
    • Describing sampling rate and sampling resolution.
  • Effects of different methods of compression on audio:
    • How compression affects audio quality, saving in files vs containers, lossy and lossless.