ABSTRACT
In a scientific sense, matter is that which occupies space. The purpose of this section is to introduce some of the terminology used in describing matter, because this is very useful in describing the world around us. The properties of matter, and the explanations for them, are dealt with in more detail elsewhere (see 29). Very familiar is the concept of the state in which matter exists. We conventionally recognize three states of matter, namely solid, liquid and gas. Here we attempt to characterize each of these states in as simple a way as possible, although in other sections we show that this task is not quite as simple as it seems.
