Lesson Notes By Weeks and Term v4 - JHS 3
INTRODUCTION TO PROGRAMMING
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INTRODUCTION TO PROGRAMMING
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Subject: Computing
Class: JHS 3
Term: 3rd Term
Week: 7
Grade code: B9.4.1.1.1
Strand code: 4
Sub-strand code: 1
Content standard code: B9.4.1.1
Indicator code: B9.4.1.1.1
Theme: COMPUTATIONAL THINKING
Subtheme: INTRODUCTION TO PROGRAMMING
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Welcome, class! Today, we are going to learn the secret language of all the digital devices we use every day—our phones, laptops, video games, and even the system for mobile money. This language is called Binary. While we humans use ten digits (0-9) to count and calculate, computers use only two: 0 and 1. Understanding how to convert our numbers into the computer's binary numbers is the first step to understanding how programming and all digital technology works. This knowledge is fundamental for anyone interested in technology, software development, or digital creativity.
A. What are Number Systems?
We need to understand two number systems for this lesson: Decimal (Base-10): This is the number system we use every day. It's called "Base-10" because it uses ten digits: 0, 1, 2, 3, 4, 5, 6, 7, 8, and 9. Each position in a decimal number has a place value that is a power of 10. *Example:* The number 345 really means: (3 x 100) + (4 x 10) + (5 x 1) (3 x 10²) + (4 x 10¹) + (5 x 10⁰) = 300 + 40 + 5 = 345 Binary (Base-2): This is the number system that computers use. It's called "Base-2" because it uses only two digits: 0 and 1. These digits are called bits (short for binary digits). Computers use binary because their electronic circuits can only be in one of two states: ON (represented by 1) or OFF (represented by 0). Each position in a binary number has a place value that is a power of 2.
Here are the first few binary place values, reading from right to left:
| Power of 2 | 2⁷ | 2⁶ | 2⁵ | 2⁴ | 2³ | 2² | 2¹ | 2⁰ | | :--- | :-- | :- | :- | :- | :- | :- | :- | :- | | Value | 128 | 64 | 32 | 16 | 8 | 4 | 2 | 1 | B. Conversion 1: Decimal to Binary