1. GCSE Computing Theory © gcsecomputing.net 1 GCSE Computing Data Representation Why Binary?

2. Learning Objectives: 2 OCR: understand that data needs to be converted into a binary format to be processed by a computer. AQA: understand that computers use the binary alphabet to represent all data and instructions GCSE Computing GCSE Computing Theory © gcsecomputing.net

3. 3 GCSE Computing GCSE Computing Theory © gcsecomputing.net The activity helps students to understand why binary representation is used by computers – it is a much more reliable way of storing and transmitting data than decimal representation. The activity can be used to introduce the whole topic of binary numbers and can be used as an ice-breaker at the beginning of the course. There is no need for students to be aware of binary place values; the column headings on the lists of digits will help you get the students in the right order.

4. 4 GCSE Computing GCSE Computing Theory © gcsecomputing.net Use three volunteers for the decimal numbers Students representing decimal digits stand up for 9, sit down for 0 and adopt an in-between posture for the other digits. Bring the volunteers to the front of the class and give each volunteer a strip of paper containing their three digit number. Make sure they stand in the right order. The numbers are: 269, 504, 734 When you give the word, the volunteers set up the first number on their lists and hold their positions while the rest of the class estimates the number. Ask for guesses of each denary number, then write these on the board and if see anyone guessed correctly.

5. 5 GCSE Computing GCSE Computing Theory © gcsecomputing.net Use three more volunteers for the binary numbers Students representing binary digits stand up for 1, and sit down for 0. Bring the volunteers to the front of the class and give each volunteer a strip of paper containing their three digit number. Make sure they stand in the right order. The numbers are: 100, 011, 101 When you give the word, the volunteers set up the first number on their lists and hold their positions while the rest of the class estimates the number. Ask for guesses of each denary number, then write these on the board and if see anyone guessed correctly.

6. 6 GCSE Computing GCSE Computing Theory © gcsecomputing.net Which group was easier to guess? B What can we learn from this? Binary is much more reliable for transmitting data.