Gain insights into basic computer anatomy, binary systems, and program lifecycles. Delve into logic building and core programming concepts with hands-on exercises and quizzes to reinforce learning.

This language-agnostic course is your guide to programming and acquiring problem-solving skills. You will start reviewing the anatomy of computers and the binary number system. You will then look at the lifecycle of a program before moving on to the core concepts of programming. Overall, the primary focus of this course is logic building within the context of computer science and programming.

Throughout each chapter, you will get hands-on experience with exercises and quizzes to solidify what you’ve learned. If you’re looking to build strong programming fundamentals then this course is the perfect place to start.

Introduction to Computers & Programming

All the data in a computer, such as numbers, text, and images, is stored in binary. Binary is a number system. It has two digits: one and zero.

> A binary digit is called a **bit**.

We will now explain how a computer stores different forms of data in binary.

# Representing numbers in binary

A bit can have two values: zero or one. A bit is said to be *on* if it has a value of one, and it is said to be *off* if it has a value of zero. To represent a number greater than one, you can use a collection of bits. 

In the illustration below, notice that each number is twice the number to its right.

**Each number in the boxes above is represented by a bit**. Suppose we have 1001 in binary. 1001 in binary means that the bit corresponding to 8 is on, the bits corresponding to 4 and 2 are off, and the bit corresponding to 1 is on. When you add all the numbers for which the bit value is 1, you get 9 in the decimal system!

In general, to find the decimal equivalent of a binary number, add all the numbers whose corresponding bits are one.

We can also convert numbers in the decimal system to binary. The illustration below explains how we can find the binary equivalent of twelve.

In general, to convert a number from decimal to binary, express it as a sum of powers of 2 (e.g. $27 = 2^{4} + 2^{3} + 2^{1} +2^{0}$). Turn the bits corresponding to these numbers on and turn the remaining ones off.  

Now, you can try the quiz below. It will help you practice finding the binary equivalent of a decimal number. 

## Practice question

Understand how information is represented in a computer.

Introduction

Getting to Know Computers

Problem Solving

Variables

Decision in Programs

Repetition in Programs

Conclusion

Information Representation in a Computer

Representing numbers in binary