1. HNC COMPUTING - COMPUTER PLATFORMS 1 Micro Teach Binary

2. HNC COMPUTING - COMPUTER PLATFORMS 2 Aims Understand how data is stored Be able to use the binary system to represent ASCII characters

3. HNC COMPUTING - COMPUTER PLATFORMS 3 How is data stored? Bits and bytes – –A computer only understands the numbers 0 or 1,true or false, or whether a switch is on or off. – –We call those 1s and 0s ‘bits’ – binary digits. – –A byte (made up of 8 bits) is enough computer memory to store a single character of data (e.g. the letter F). – –Half a byte is known as a nibble (made up of 4 bits) – –Using the ASCII code, for instance, the letter F is 70 and has a bit pattern of 01000110.

4. HNC COMPUTING - COMPUTER PLATFORMS 4 How is data stored? Cont. ASCII for Capital Letters 65A 78N 66B 79O 67C 80P 68D 81Q 69E 82R 70F 83S 71G 84T 72H 85U 73I 86V 74J 87W 75K 88X 76L 89Y 77M 90Z American Standard Code for Information Interchange (ask-ee) is a code which represents English characters as numbers. Each letter is assigned a number. For example, A = 65. Most computers use ASCII codes. This makes it possible to transfer data from one computer to another by changing the ASCII code into a binary pattern.

5. HNC COMPUTING - COMPUTER PLATFORMS 5 How is data stored? Cont. Decimal When we write numbers in the decimal system, we write them in columns. Each column is ten times bigger than the one before (right to left). Tens of millions millions100000s10000s1000s100s10s1s 1010 So 1010 is 1000 plus 10 = 1010. Tens of millions millions100000s10000s1000s100s10s1s11010 11010 would be 10000 plus 1000 plus 10 = 11010.

6. HNC COMPUTING - COMPUTER PLATFORMS 6 How is data stored? Cont. In the binary system, everything is based on 2s, not 10s, so each column is twice as big as the one before. 128s64s32s16s8s4s2s1s 1010 So 1010 in binary is 8 plus 2 = 10.128s64s32s16s8s4s2s1s11010 11010 would be 16 plus 8 plus 2 = 26.

7. HNC COMPUTING - COMPUTER PLATFORMS 7 You have ago

8. HNC COMPUTING - COMPUTER PLATFORMS 8 How is data stored? Cont. All computer data is stored in binary form. This not only includes text, but images, sounds and movies as well. The more complex the data, the more memory is used to store it. This does not take up as much memory… …as this.

9. HNC COMPUTING - COMPUTER PLATFORMS 9 Conclusion We discussed how data is stored How to use the binary system to represent ASCII characters