Karma to put it simply, means action. Any action that we do is karma. And as we sow, so we reap. Our actions give us their effects as well, which we need to accept.
Like a company having acceptable and not-acceptable practices and behavior, so should life have right? Like, how much ever technically advanced we become, to harm another person for my own selfish ends, cheat, lie, kill can never become good.
In Vedas, karmas are classified into two broad groups - “Punya Karma” or “Paapa Karma”. Punya Karma is a karma that Vedas consider acceptable, and produces good results for us and others. Paapa Karma is a karma that Vedas consider un-acceptable, and produces bad results for us and others. We need to reap the result of our punya and paapa karmas.
Sometimes in life (and only sometimes), we see good things happening to us without trying very hard for it – that is the result of our past Punya. Conversely, we see ourselves getting into problems without much of our fault – that is the result of our past Paapaa.
This is not to say that everything in life is determined – it isn’t. Between major milestones which are determined to an extent, we have our lives to ourselves to live properly. If we don’t use that and make wrong choices again, then it’s our fault. Besides, it’s not actually important as to what we face; it’s only important how we respond to it. The response can help an individual advance in his goal/mission or set him back by many yards. This is a topic where our understanding would get more refined as we travel further.
We take various births as long as we have Punya or Paapa karmas whose effects we haven’t yet borne. And that account is almost always evergreen – except if we consciously try and find ways to close it. This is because, even when we do something good, we do so many things that would result in various Punya and Paapaa. The rate at which we earn this is so fast, but we can’t really expend it at the rate at which we earned it.
Let’s see a little example for it. Assume that I am going to serve food for the needy - certainly a noble deed, no doubt. So, it should give me Punya right? Yes, it will. But I would earn many other Punya and Paapa in the process as well. I started my car and in my hurry to reach the place, yelled at the cook who cooked the food late (paapaa). I thought how noble I was and how I am superior to many others by my noble deeds (paapaa). I stopped to give money to some begging children on the way (Punya). Finally I did serve some needy people, which is a great deed (punya). All these in-process punya and paapa has also to be spent ultimately. So, even in this small example, even with the very limited combination of possible tasks, we see that we earn more than we can spend. Imagine this for all activities for the whole life! And for many births!
Since we have an evergreen account of karmas to exhaust, we take repeated births in this world to sort of close our karmic accounts by taking their effects and have another chance at advancing towards the ultimate goal of a jeevathma.
So, how do we utilize this “another chance” of a birth? For that we need to know what the ultimate goal of a jeevathma is.