Cambrian Explosion: The theory holds that, beginning some 545 million years ago, an explosion of diversity led to the appearance of a huge number of complex, multi-celled organisms over a relatively short period of 5 million to 10 million years. Moreover, this burst of animal forms led to most of the major animal groups we know today, that is, every extant Phylum (group of animals based on general body plan, as well as developmental or internal organizations). The Cambrian explosion gave rise to the first shelled animals and animals with exoskeletons.

Creationism: Creationism is belief in the literal interpretation of the account of the creation of universe and of all living beings described in the scripture. Since this term is popular in the West, the word “scripture” refers primarily to the Bible.

Fossils: Fossils are the preserved remains or traces of animals, plants, and other organisms from the remote past.

Geocentrism: In astronomy, the geocentric model of the universe is the theory that the Earth is the center of the universe and other objects go around it. Belief in this system was common in ancient Greece. Most of ancient Greek philosophers assumed that the Sun, Moon, stars, and planets circle the Earth.

Heliocentrism: In astronomy, heliocentrism is the theory that the Sun is at the center of the Universe. Historically, heliocentrism was opposed to geocentrism. Though discussions on the possibility of heliocentrism are quite old, it was not until the 16th century, that the Polish mathematician and astronomer Nicolaus Copernicus presented a fully predictive mathematical model of a heliocentric system.

Intelligent Design (ID) Movement: The movement is a campaign, prominent in the US, that calls for broad social, academic and political changes derived from the concept of “intelligent design” (the theory of “intelligent design” holds that certain features of the universe and of living beings are best explained by an intelligent cause, not by an undirected process such as natural selection).They try to promote public awareness of this concept, persuade policymakers to include its teaching in high school science classes. Proponents believe that the theory of evolution implies that humans have no spiritual nature, no moral purpose, and no intrinsic meaning. The movement’s proponents seek to defeat the materialist world view represented by the theory of evolution.

Orkut: Orkut is a free-access social networking service owned and operated by Google. The service is designed to help users meet new friends and maintain existing relationships.

Photosynthesis: Photosynthesis is a process that converts carbon dioxide into organic compounds, especially sugars, using the energy from sunlight. Photosynthesis occurs in plants, algae, and many species of bacteria.