The earliest Indian civilization began on the Indus River. Later, the Aryans came along and arrived in Northern India. These people changed the way people lived and evolved. The Aryans changed India by separating the rich and the poor with a social arrangement. This new way of life lead to the invention of the choker appliance and a unique number system. To begin, the Aryans created a caste system that separated Indians into groups in which people are born in and cannot leave. The system dictates what job you have and whom you can marry. In ancient times the philosophers believed that the Aryans were the first civilization to be racist. The Aryans were a light-skinned people and they thought they were much better than the dark-skinned people they encountered in India so they created this system. At the very bottom of the chain was the Pariahs or Untouchables. They performed the all the dirty work. Above them came the Sudras or the unskilled laborers. The Sudras did manual work and had few rights. Further up, lay the Vaisyas a.k.a. the common class. This class consisted of farmers and merchants. The top three ranks were the priests, warriors, and rulers. These kinds of people ruled over India and controlled its government.At around the 4th century BC, the ancients interestingly used words to express numbers. In fact, the word arms were used to convey the number 2 because humans have two arms. However, words couldn’t be used for calculations so, at around 10 BC, they were replaced by symbols. In contrast to the Indians, the Babylonians only had a limited number of symbols. So, to write five, it took five symbols but in the Indian system, it took only one symbol. It was the Indian system of nine digits that we use today. Looking back in time, nearly two hundred years ago, the making of cotton helped spark the industrial revolution and provides the world with fabric for our modern day society. Cotton was first domesticated five-thousand years ago in the Indus River Valley. Each cotton bloom contained seeds that were extremely difficult to extract so they invented more efficient mechanical device called the choker. The choker would pinch the cotton balls so they could extract the seeds. Indian craftsmen also invented another too that would give their cotton a particular quality. Although most historians believe the origins were in China, the earliest recorded appearance was in India. Without cotton we would not have t-shirts or wear are favorite pants: blue jeans! For seven thousand years India has provided the world with its riches. India has also furnished the world with contributions in literature, mathematics and science.