Basic States of Matter:

Thousands of years ago, in the time of the ancient Roman and Greek civilization, scientists believed that all things in the material universe consisted of combination of four "elements": water, earth, air, and fire. According to this theory, various proportions of these four "elements" provide materials their exclusive properties. This was used to describe why gold is distinct from salt that in turn is dissimilar from oil. This seems primitive to us, though the ancients had keen minds. They were particularly good at examining things and at seeing the "big picture."

It is fascinating to speculate on what may have happened when those scientists had been permitted to enlarge on their knowledge for all the time between, say, 100 A.D. and nowadays. Though, such unimpeded progress did not take place. After the Roman civilization refused, the whole Western world came under a kind of collective trance in which superstition and religious dogma prevailed. At its worst, this system was too strict that a mathematician, philosopher, or scientist who voiced an opinion distinct from the conventional wisdom was punished rigorously. Some were even put to death.

During and after the regeneration, whenever scientific logic became a respected mode of thought once again, the physical scientists discovered that there are many more than four elements and that even these elements are not the basic constituents of matter. Though, there are three basic states of matter familiar by scientists nowadays, and these are analogous, in a crude kind of way, to three of the original "elements." These states, also termed as phases, are termed as solid (i.e., the analog of earth), liquid (the analog of water), and gaseous.

A sample of matter in the solid phase will maintain its shape unless subjected to vicious impact, placed under stress, or subjected to high temperatures. Illustrations of solids are rock, steel at room temperature, water ice, wood, salt, and plastic at room temperature.