What is a number system? It is a set of symbols used for counting and performing calculations. Today we all use the so-called Hindu-Arabic number system to represent numbers in our daily life i.e., numbers formed by the digits 0,1, ... 9, which is very convenient for us to record counting numbers and do calculations. In this module, we will go back to ancient times and take a look at different number systems in different civilisations so as to appreciate the wisdom of the ancient people and learn how the ancient number systems evolved into the one we all use in modern times. We will introduce the following ancient number systems:

1. Egyptian Number System

2. Babylonian Number System (Where is Babylon?)

3. Greek, Roman and Chinese Number Systems

4. Mayan and Hindu-Arabic Number Systems (Where can we find the Mayan civilisation?)

Moreover, we will also discuss some other number systems, which are specially designed for computer applications. They are

1. Binary Number System

2. Hexidecimal Number System