ABSTRACT
What is air? Most of us would have little difficulty in quickly answering this question by stating that air is the oxygen that we breathe-the substance that we need to sustain life.
Taking our definition of air to the next level and beyond, we might state that air surrounds us-air is virtually everywhere; air is that substance we feel against our faces and skin when the wind blows; air is that gas that we use to fill our automobile tires; air is necessary for combustion to take place; hot air lifts our balloons; air under pressure (pneumatic air) powers our tools and machines; air can be either warm or cold or just about right; air is air-what more needs to be said? A lot more.
