Year 11 · ICT · Spring 2

Paper 1 theory revision · Lesson 5 of 5

A full Paper 1

Exam practice1.3 Operating systems6.9 Computers in the retail industry7.4 Implementation

Year 11 · ICT · Paper 1 theory revision · Lesson 5 of 5

You will learn to

  • Complete a full Paper 1 in 1 hour 30 minutes.
  • Use the timing plan: about a mark a minute, with 10 minutes to check.
  • Use the mark scheme to mark the paper and update your tracker.

Year 11 · ICT · Paper 1 theory revision · Lesson 5 of 5

Success criteria

You have got it when you can say:

  • I can finish the paper and check it in the time given.
  • I can answer every question, with no blanks.
  • I can list my three reddest theory points.

Year 11 · ICT · Paper 1 theory revision · Lesson 5 of 5

Retrieval starter

Questions from before. Write your answers, then show them.

  1. Last lesson

    A touch screen that senses the electricity in your finger is…

    A CapacitiveB Infra-redC Resistive

    A. Capacitive

  2. Last unit

    An anchor (bookmark) link…

    A Opens a new siteB Jumps to a place on the same pageC Opens an email

    B. Jumps to a place on the same page

  3. Earlier this year

    Extreme test data is…

    A Typical dataB Outside the rangeC At the edges of the allowed range

    C. At the edges of the allowed range

Year 11 · ICT · Paper 1 theory revision · Lesson 5 of 5

Key words (1 of 7)

Software
The programs (sets of instructions) that run on the hardware.
System software
Software that runs and maintains the computer, such as the operating system and drivers.
RAM
Random access memory: volatile memory holding the programs and data in use.
ROM
Read-only memory: non-volatile memory holding the start-up instructions.

Year 11 · ICT · Paper 1 theory revision · Lesson 5 of 5

Key words (2 of 7)

Operating system
System software that manages the hardware, files and programs, and gives the user an interface.
GUI
Graphical user interface: windows, icons, menus and pointers.
CLI
Command line interface: the user types text commands.
Computer model
A program that uses rules and formulas to act like a real system.

Year 11 · ICT · Paper 1 theory revision · Lesson 5 of 5

Key words (3 of 7)

What if
Changing a model's inputs to see what would happen.
EFT
Electronic funds transfer: moving money between accounts electronically.
EFTPOS
Electronic funds transfer at point of sale: the card terminal at a till.
Re-order level
The stock level at which a new order is sent to the supplier.

Year 11 · ICT · Paper 1 theory revision · Lesson 5 of 5

Key words (4 of 7)

NFC
Near field communication: very short-range radio used for phone payments.
Systems life cycle
The stages used to create a new system: analysis, design, development and testing, implementation, documentation, evaluation.
Systems analyst
The person who studies the current system and plans the new one.

Year 11 · ICT · Paper 1 theory revision · Lesson 5 of 5

Key words (5 of 7)

System specification
A list of the hardware and software the new system needs.
Field
One item of data in a record, such as Surname.
Check digit
An extra digit calculated from the other digits, used to detect input errors.
Data capture form
A paper or on-screen form used to collect data.

Year 11 · ICT · Paper 1 theory revision · Lesson 5 of 5

Key words (6 of 7)

Test plan
A table listing each test, its data, the expected and actual outcomes and any remedial action.
Live data
Real data from the organisation, used to test the system with known results.
Direct changeover
The old system stops and the new one starts immediately.
Parallel running
Old and new systems run together until the new one is trusted.

Year 11 · ICT · Paper 1 theory revision · Lesson 5 of 5

Key words (7 of 7)

Pilot running
The new system is tried in one branch before the rest.
Phased implementation
The new system is introduced one part at a time across the organisation.

1.3 Operating systems · The explanation · step 1 of 10

What an operating system does

An operating system (OS) is the system software that runs the computer. It is loaded when the computer starts.

It manages memory, files and folders, input and output devices, security (user accounts) and the running of programs.

It also gives the user an interface: the way the user and the computer communicate.

1.3 Operating systems · The explanation · step 2 of 10 · part 1 of 2

Command line and graphical user interfaces

A command line interface (CLI) is text only. The user types commands, such as `copy report.docx backup`.

A graphical user interface (GUI) uses windows, icons, menus and a pointer (WIMP). Smartphones use a post-WIMP GUI where you tap and swipe instead of using a pointer.

CLIGUI
AdvantageThe user has direct control and can do things the GUI cannot; uses little memory and processing powerEasy to learn, no commands to remember, so good for beginners
DisadvantageMust learn and remember commands; typing errors stop commands workingUses more memory and processing power; some advanced settings are hidden
Typical userNetwork manager, technician, programmerOffice worker, student, home user

1.3 Operating systems · The explanation · step 2 of 10 · part 2 of 2

Command line and graphical user interfaces (continued)

!Watch out

Compare both sides; a description alone is not enough. "A GUI is easier to use than a CLI because the user does not need to remember commands."

1.3 Operating systems · The explanation · step 3 of 10 · part 1 of 2

Dialogue-based and gesture-based interfaces

A dialogue-based interface lets the user talk to the computer. Voice assistants in phones, smart speakers and cars use it. The computer replies with speech.

A gesture-based interface reads body movements, such as a hand wave or a swipe in the air, using a camera or motion sensor. Games consoles and some cars use it.

1.3 Operating systems · The explanation · step 3 of 10 · part 2 of 2

Dialogue-based and gesture-based interfaces (continued)

Dialogue-based (voice)Gesture-based
AdvantageHands-free, so safer when driving; helps people with limited movementNo touching, so more hygienic (e.g. in a hospital); feels natural
DisadvantageBackground noise and accents cause errors; limited set of commandsAccidental movements can trigger commands; user must learn the gestures
Example"Call home" in a carWaving to skip a song on a car screen
e.g.Example
Exam style: "A driver wants to change the radio station. Give one advantage of a dialogue-based interface." Answer: The driver can keep both hands on the wheel, because they speak the command instead of pressing buttons.

6.9 Computers in the retail industry · The explanation · step 4 of 10 · part 1 of 2

POS and EFTPOS terminals

A point of sale (POS) terminal is the checkout till. It has a barcode reader, screen, keypad, receipt printer and cash drawer. It is linked to the shop's stock database.

An EFTPOS terminal (electronic funds transfer at point of sale) is the card reader at the till. It takes card payments.

Advantages of card paymentDisadvantages of card payment
No need to carry large amounts of cash, which is saferCard can be cloned or stolen; shoulder surfing of PIN
Faster for the shop; less cash to count and bankShop pays fees to the card company
Payments recorded, so easy to track spendingFails if the network is down

6.9 Computers in the retail industry · The explanation · step 4 of 10 · part 2 of 2

POS and EFTPOS terminals (continued)

e.g.Example
Paying by chip and PIN: 1. Card inserted; chip is read. 2. Customer types PIN; it is checked against the chip. 3. Terminal contacts the customer's bank (the card issuer). 4. Bank checks the card is valid and there are enough funds. 5. If yes, the payment is authorised and the amount is reserved. 6. Money is transferred to the shop's account, and a receipt is printed.

6.9 Computers in the retail industry · The explanation · step 5 of 10 · part 1 of 3

Automatic stock control

The shop's database stores each product's barcode number, name, price, stock level and re-order level (the number at which more must be ordered).

6.9 Computers in the retail industry · The explanation · step 5 of 10 · part 2 of 3

Automatic stock control (continued)

e.g.Example
1. A carton of milk is scanned at the POS. 2. The barcode number is looked up in the stock database. 3. The name and price are sent back to the till. 4. The stock level is reduced by 1 (e.g. from 21 to 20). 5. The stock level is compared with the re-order level (20). 6. Stock is now at the re-order level, so an order is sent to the supplier automatically. 7. A flag is set so the item is not ordered twice. 8. When the delivery arrives, the stock level is increased and the flag is cleared.

6.9 Computers in the retail industry · The explanation · step 5 of 10 · part 3 of 3

Automatic stock control (continued)

?Why?

Shelves stay stocked without staff counting items, and the shop does not tie up money in too much stock.

!Watch out

Write "stock level is compared with the re-order level". "The computer knows it is low" gets no mark.

6.9 Computers in the retail industry · The explanation · step 6 of 10 · part 1 of 2

Contactless and NFC

Contactless cards contain an RFID chip and antenna. The customer holds the card near the reader. Payments are limited to a set amount (often 50 euros), and the PIN is asked for every few payments.

NFC (near field communication) is a type of very short-range radio, usually under 4 cm. Phones and smartwatches use NFC to pay, pretending to be a contactless card.

6.9 Computers in the retail industry · The explanation · step 6 of 10 · part 2 of 2

Contactless and NFC (continued)

Phone payments use tokenisation: a one-time code is sent instead of the real card number, and the user unlocks the phone with a fingerprint or face first.

AdvantagesDisadvantages
Very fast, so shorter queuesStolen card can be used for small payments without a PIN
No PIN to be seen by shoulder surfing for small paymentsEasy to spend without noticing
Phone payments are protected by biometrics and tokensCriminals with a reader may try to read cards in a crowd

The explanation · 4 more steps

More on the lesson page

The lesson page has the rest of the explanation, step by step:

  • Internet shopping
  • Four ways to change over
  • Advantages and disadvantages
  • Choosing the right method

Open the lesson page

Year 11 · ICT · Paper 1 theory revision · Lesson 5 of 5

Quick quiz · 1 of 3

ANPR reads…

  1. A Barcodes
  2. B Number plates
  3. C Fingerprints

B. Number plates

Automatic number plate recognition, in car parks and on roads.

Year 11 · ICT · Paper 1 theory revision · Lesson 5 of 5

Quick quiz · 2 of 3

In automatic stock control, the stock level drops when…

  1. A The manager counts
  2. B The shop closes
  3. C The barcode is scanned at the till

C. The barcode is scanned at the till

When stock reaches the reorder level the system orders more.

Year 11 · ICT · Paper 1 theory revision · Lesson 5 of 5

Quick quiz · 3 of 3

A spreadsheet weather model is used because…

  1. A It is always exactly right
  2. B It is cheaper and safer than real experiments
  3. C It needs no data

B. It is cheaper and safer than real experiments

Models predict; they are only as good as their data and rules.

Year 11 · ICT · Paper 1 theory revision · Lesson 5 of 5

Exit ticket

Answer on paper before you go. Then check.

  1. EFTPOS means…

    A Posting a chequeB Paying by card at the tillC Sending an email

    B. Paying by card at the till Electronic funds transfer at point of sale.

  2. Parallel running means…

    A Old and new systems run together for a whileB Switching over in one goC Testing in one branch first

    A. Old and new systems run together for a while Safe but twice the work. Direct changeover is quick but risky.

Year 11 · ICT · Paper 1 theory revision · Lesson 5 of 5

Homework and the challenge

Homework

Quiz mixes: 'IGCSE ICT: 10 at random' every evening.

End-of-unit challenge

The spring mock: a full Paper 1 under time.