# How Computers Encode Text Using Binary

#### Storyboard Text

• Yes! Except, the one's and zero's are called binary code. Come over and I'll explain it more!
• 01001000 01101001
• Because that is how computers read letters!
• It means 'Hi' in computer text, Aaron
• Sarah
• So are you saying that computers encode text by using one's and zero's?
• Wow! Why is it in one's and zero's?
• What does that mean Sarah?
• Sarah 1: Every single letter, character and symbol has an allocated decimal value. Just like languages, there are different types of decimal value translations. But the one most used (and the one we are using now) is ASCII decimal value. For example, the letter B has an ASCII decimal value of 66.
• 2 Hours Later...
• Decimal Value (ASCII)B = 66C = 67Z = 90
• Sarah 3: Good question Aaron. Let me take you to my work table.
• Sarah 1: Once the decimal value is known, the computer can convert it to binary code. For example, 66 = 01000010
• Aaron 2: Alright! But how does binary code work?
• Binary Code:B = 66 = 01000010C = 67 = 01000011Z = 90 = 01011010
• Aaron 2: You said that the last five numbers in binary code represent the actual letter. Well, how does the numbers change to a letter?
• Sarah 3: As you know, each letter in the English alphabet has an allocated spot. For example, A is the first (1) letter in the alphabet, H is the eighth (8) letter. In binary, a letter is represented by showing the place it is allocated in the English alphabet. For example,00001 = 1 = A. 010000 = 8 = H
• Capital or lowercase010= Capital 011 = Lowercase
• 01000010
• The letter: E.g. c, d, f.
• Sarah 1: There are 8 numbers in a binary number. The first three represent whether the letter is a capital or lowercase. If it starts like 010, then it is a capital. If it starts like 011, then it is a lowercase. The next five represent the actual letter.
• Aaron 1: I understand! But Sarah, how does 01000 = 8? Doesn't it just equal 1?
• Sarah 3: The number that is allocated to the binary code is only counted when it is ON. To turn the binary ON, you change the 0 to 1. When the binary is 0, it is OFF and the allocated number isn't counted.1 = ON0 = OFFSo 8 would equal 01000 as 8 is the allocated number for that position. 00100 would equal 4 as 4 is the allocated number for that position.
• Sarah 2: Well, each place in the binary code has an allocated number as well. Going from right to left, you multiply the previous number by 2. So, 00000001 = 100000010 = 200000100 = 4
• 128 64 32 16 8 4 2 1 0 1 0 0 0 0 1 0 OFF ON OFF OFF OFF OFF ON OFF
• Aaron 1:Thanks Sarah, I think I understand. But can you please summarise it?
• Aaron 3:Wow that's coo-. Wait! I need to head to soccer practice, I'm nearly late! Thanks for all the help Sarah.
• Sarah 2: Sure thing! Every letter has an allocated decimal value (ASCII value). For example, B = 66. This value is then translated into an 8 numbered binary code (01100011). Computers can only read binary code, so when they see these numbers, they know what letter to present on the screen. 1 = ON and 0 = OFF. You should also keep in mind that every place in a decimal number has a value. 00000010 = 2 as the second last place has 2 as it's allocated number. 00010000 = 16 as the fourth place has 16 as it's allocated number.
• Sarah 4: No problem, have fun at soccer practice!