Book excerpt: This book introduces the binary, octal and hexadecimal numbering systems used in computer science and computer programming. It introduces how numbers are represented in each of these systems, how to convert between them (and to and from base 10). In this book, among other things, you will learn: * What are number bases (also known as radixes) * What is binary (base 2) * How to convert binary numbers to denary (base 10) * How to convert denary numbers to binary * What is octal (base 8) * How to convert octal numbers to denary * How to convert denary numbers to octal * Why many programmers and computer scientists use octal * How to convert octal numbers to binary * How to convert binary numbers to octal * What is hexadecimal (base 16) * How to convert hexadecimal numbers to denary * How to convert denary numbers to hexadecimal * Why many programmers and computer scientists use hexadecimal * How to convert hexadecimal numbers to binary * How to convert binary numbers to hexadecimal * Is there a reason to prefer octal over hexadecimal or vice-versa?