Dashas in astrology is the divisions of time that show how planetary influences will play out in a person's life. There are various dashes, each with its own unique meaning. The Dasha system is an important tool for understanding the karma of a person's past lives and how it will affect their current incarnation.
There are many factors that go into determining which dasha a person is currently experiencing. The most important is the position of the planets at the time of birth. The planets each rule over a certain period of time, and the order in which they rule is determined by their order in the solar system. The planets move through the signs of the zodiac at different rates, so the timing of the dashes also varies from person to person.