A2.1 Code is a list of exact steps
Code is a set of instructions a machine follows exactly, one after another. An algorithm is the list of steps. If a step is missing or in the wrong order, the machine gets it wrong — it cannot guess.
Example
Write arrow code to move a robot two squares right, then one square up.
- → → ↑
- Run it with a finger on a grid: right, right, up. Did it land where you wanted?
- If not, find the arrow that is out of place and fix it.
A2.2 How coding and new technology change daily life
Example
Name what happens because of code in a traffic light, a hearing aid and a talking toy.
- Traffic light: code changes the colours in order, so cars and walkers take turns.
- Hearing aid: code makes quiet sounds louder, so a person can hear voices.
- Talking toy: code plays a sound when a button is pressed.
Remember: Each one follows steps someone wrote.
Summary
- Code = exact steps in order.
- Machines cannot guess a missing step.
- Traffic lights, hearing aids and toys follow written steps.