code

Everyday

1. A code is a system of letters, numbers or signs used to send secret messages. tree →
2. Code is the instructions written for a computer, and coding is writing them. tree →
3. A code is a set of numbers or letters used to identify or unlock something, like a door code or postcode. tree →
4. A code is a set of rules: a dress code, a code of conduct. tree →

In the lessons

In computing lessons, code is a sequence of instructions (algorithm) a computer follows exactly, with loops and conditions. In maths, codes like «A=1, B=2» use patterns. In safety: never share your PIN code or passwords. Phrases: secret code, crack a code, break the code, postcode, zip code, Morse code, dress code.

Examples

• We wrote a secret message in code. tree →
• Can you crack my code? tree →
• I learned to code a simple game. tree →
• The door opens when you type the code. tree →
• What is your postcode? tree →
• In Morse code, SOS is three dots, three dashes, three dots. tree →
• The school has a dress code. tree →
• My code had a bug, so I fixed it. tree →
• He was a very wise little boy, and he knew that, in Uncle Remus's eyes, he had been guilty of a flagrant violation of the family code. tree →

Note

Code for programs is usually uncountable: «write some code», not «write a code». Postcode (UK, Australia, Ireland: Eircode) = zip code (USA) = postal code (Canada). A cipher is a code that swaps letters.