The popular understanding of karma is that if you do good things, good things will happen to you. If you do evil, bad things will happen to you.
What people perceive as good or evil, however, varies with their values. Your parents, your friends, your work, and the teachings of religious or spiritual groups with whom you affiliate influence your values. You formulate some of your own values through your reflection and experience. So there are very different notions of what constitutes good and bad karma between individuals and between groups.
Karma as presented in religion takes this cause and effect relationship to a deeper level. Some religions predict that you will reap a heavenly or hellish experience in the hereafter based on your deeds in human life. Other religions believe that you may obtain a good rebirth or even freedom from birth and death if you live well and meditate successfully, or have a horrendously miserable human birth or even transmigrate into animals or plants if you live an evil life and don't meditate.
Religions make these predictions based on their particular standards of what constitutes right thought, words and deeds. Opinions vary widely on what will get you into heaven and what that heaven world might be like once you get there. Some religions even hold that heaven worlds are illusory, and that union with the spiritual origin is the only worthy goal.
The Mudrashram® lineage teaches that karma is the raw material of the unconscious mind that gives rise to desire-driven impulses, fantasies or behavior. Depending on where karma layers on the continuum of the mind, it expresses in four different ways. These four types of karma are:
Adi Karma - layered behind the ensouling entity, this is the template of potential spiritual development. In the Western esoteric tradition, these are referred to as your future Initiations, the unfolding pattern of your Soul moving ever closer to Mastery.
Sinchit Karma - layered behind the spirit in the channels of the Nada, it exists as impressions of passions, fantasies and unfulfilled desires. In Christian religious groups, these impressions are known as sins that separate the spirit from God.
Kriyaman Karma - layered behind the nuclei of the vehicles, it is a reservoir of unfinished goals. It also contains the consequences of your past actions and saves your current thoughts, words, and deeds for future fruition. This karma is created by your choices, the activity of your will. This is the popular 'as you sow, so shall you reap' vision of karma.
Pralabdha Karma - these are the issues and circumstances in your life that are outside of your voluntary control. This karma is layered upon the template of your human life in your causal body. This is popularly known as your Fate.