What we refer to as wax today is any long hydrocarbon chain that is:

Traditionally, wax referred to only substances that occurred in nature - primarily beeswax but also waxes from plants (such as bayberry wax, though also from soy). This classification has expanded with sources of wax from minerals (montan wax), petroleum processing (paraffin wax) and chemical synthesis (such as polyethylene).

While the main component of wax is hydrocarbon chains, waxes from natural sources (plants and animals) are often more complex and contain esters, fatty acids, and alcohols.

Often, the waxes used in candle makings are combinations of several types of wax to bring out certain properties such as melting point, smell (as is the case with beeswax and bayberry wax), texture, and smoke production. The higher the melting point, the less oil in the wax and thus the wax is harder and more brittle.

The most common wax in use today is that of paraffin wax. Paraffin is from Latin "parum" meaning "few or without" and "affinis" meaning "connection or attraction" ("affinis" is the root of the word "affinity"). Plants naturally produce wax on leaves and stems to protect themselves from weather (excessive moisture or drought). As these plants decayed over millions of years and became oil. The inert nature of wax caused it to remain separate from the rest of the oil and were suspended within the oil. Upon processing of the oil into gasoline, kerosene, and other oils, the wax is a byproduct and less than desirable (do you want wax in your gas tank?). Refineries process the wax into either a clear liquid or a milky white slab. These slabs are graded by melting point and are about 10 or 11 pounds in weight. Because the wax is not the primary (or even secondary) product for the refinery packaging is not of great importance. Thus, from one batch to the next (or one refinery compared to another refinery) size, color, shape, and texture may vary.

Beeswax is historically one of the most well known waxes. The wax here is actually a refined honey. As bees eat honey the sugar is converted into wax which is then secreted under the abdomen. From this, honey bees build hives. Beeswax is collected when bee keepers collect honey and remove the caps on the honey comb.