The world's oldest polytheistic religion
Hindus believe in a term called karma. Karma is your good and bad actions having a good or bad result to your life. Karma becomes important when tied together with reincarnation, a continuous cycle in which the soul is reborn over and over again according to the law of action and reaction. At death, many Hindus believe the soul is carried into a new physical body which is usually human. If you lived a good life, then in your next life you will be rewarded by being born into a rich or powerful family. If you lived a bad life, then in your next life you will be born into a poor family or family with a bad job. Hindus believe in following this cycle until they live the best life possible.
Hinduism does not have one holy book, but rather hundreds of books written by famous Hindu thinkers. The oldest and most important are called the Vedas.
Most Hindus worship in their homes, and have small shrines built in their home for a god that is special to their family. There are large temples for large Hindu worship events.
Hinduism has many festivals to celebrate different events of the year. One of the largest in the festival of lights or Diwali.