Catalysts are elements or compounds that increase the speed of a chemical reaction without actually being used up in the reaction. Humans have used the process known as catalysis long before they understood the mechanics behind it. Some examples include soap-making, the fermentation of wine to vinegar, and the leavening of bread are all processes that involve catalysis. Ordinary people were using these procedures in their everyday lives without knowing that catalysis was involved.

The term catalysis was proposed in 1835 by the Swedish chemist Jöns Berzelius. The term comes from the Greek words for "down"--kata--and "loosen"-- lyein . Berzelius explained that he meant by the term catalysis "the property of exerting on other bodies an action which is very different from chemical affinity. By means of this action, they produce decomposition in bodies, and form new compounds into the...