Year 7 · Summer 2
Raid: Code for a Cause · Lesson 3 of 5
Designing for an audience: layout, colour and typography
TheoryTopic 5 Representing images
Year 7 · Raid: Code for a Cause · Lesson 3 of 5
You will learn to
- Identify who a poster is for and what its one message is.
- Explain how layout, colour and font choices help or hurt a design.
- Compare three posters and explain which one works best for its audience.
Year 7 · Raid: Code for a Cause · Lesson 3 of 5
Success criteria
You have got it when you can say:
- I can name the audience and the message of a poster.
- I can spot a poster with too many colours or text too small to read.
- I can use the rules: one message, two colours, text big enough to read from the back.
Year 7 · Raid: Code for a Cause · Lesson 3 of 5
Retrieval starter
Questions from before. Write your answers, then show them.
- Last lesson
A logo must look sharp on a pen and on a billboard. Best stored as…
A A vectorB A bitmap
A. A vector
- Last unit
Which shape is used for OUTPUT total?
A ParallelogramB DiamondC Rectangle
A. Parallelogram
- Earlier this year
A face-recognition model works badly on faces unlike its training photos. This is…
A A syntax errorB Bias from unrepresentative training dataC Overflow
B. Bias from unrepresentative training data
Year 7 · Raid: Code for a Cause · Lesson 3 of 5
Key words (1 of 2)
- colour depth
- Bits per pixel. Sets how many colours are possible.
- Pixel
- The smallest single-colour dot of an image.
- Bitmap
- An image stored as a grid of pixels.
- Resolution
- Number of pixels: width × height.
Year 7 · Raid: Code for a Cause · Lesson 3 of 5
Key words (2 of 2)
- Metadata
- Data about data, like an image's width and height.
- Vector
- An image stored as shapes and instructions.
The explanation · step 1 of 2
More colours = more bits per pixel
Bits per pixel = colour depth. Same rule as before: n bits give 2ⁿ colours.
| Colour depth | Colours | Use |
|---|---|---|
| 1 bit | 2 | Black and white |
| 2 bits | 4 | Very early games |
| 8 bits | 256 | GIFs, retro graphics |
| 24 bits | about 16.7 million | Normal photos |
The explanation · step 1 of 2
The maths: How many colours?
The explanation · step 2 of 2 · part 1 of 2
How 24-bit colour works (RGB)
Screens mix three lights: Red, Green, Blue. Each gets 1 byte (0–255). 3 × 8 = 24 bits.
| Colour | Red | Green | Blue | Hex |
|---|---|---|---|---|
| Black | 0 | 0 | 0 | #000000 |
| White | 255 | 255 | 255 | #FFFFFF |
| Red | 255 | 0 | 0 | #FF0000 |
| Yellow | 255 | 255 | 0 | #FFFF00 |
| Orange | 255 | 128 | 0 | #FF8000 |
The explanation · step 2 of 2 · part 2 of 2
How 24-bit colour works (RGB) (continued)
Why is red + green = yellow? Mixing light adds colours. Mixing paint takes them away. Screens make light.
Year 7 · Raid: Code for a Cause · Lesson 3 of 5
Quick quiz · 1 of 3
A shop keeping your data for 20 years 'just in case' breaks…
- A Data protection law
- B The Computer Misuse Act
A. Data protection law
Storage limitation: data must not be kept longer than needed.
Year 7 · Raid: Code for a Cause · Lesson 3 of 5
Quick quiz · 2 of 3
Spreading ransomware that locks a company's files is which CMA offence?
- A Section 1
- B Section 3
- C Section 2
B. Section 3
Section 3: unauthorised acts that impair a computer. Up to 10 years.
Year 7 · Raid: Code for a Cause · Lesson 3 of 5
Quick quiz · 3 of 3
Which is the Spanish equivalent of the Data Protection Act 2018?
- A Código Penal art. 264
- B Ley de Propiedad Intelectual
- C LOPDGDD (Ley Orgánica 3/2018)
C. LOPDGDD (Ley Orgánica 3/2018)
With the EU GDPR, the LOPDGDD is Spain's data protection law.
Year 7 · Raid: Code for a Cause · Lesson 3 of 5
Exit ticket
Answer on paper before you go. Then check.
An email link says 'brightwell.example' but hovering shows 'brightwe11-login.xyz'. This is…
A A red flag: the real address is differentB Safe because it has HTTPSC Normal for banks
A. A red flag: the real address is different The visible link text can say anything. The real address is what matters.
A photo is licensed CC BY-NC. Can a company use it in a paid advert?
A No: NC means non-commercialB Yes, if they credit the creator
A. No: NC means non-commercial NC forbids commercial use, even with credit. They would need to ask permission.