Sri Sri Ravi Shankar:
See, we do many actions but their impressions do not stay on our minds. For example, if I ask you a week later, 'What did you have for breakfast on Saturday', you will not remember, unless it was an occasion or you had a fight!
If someone asks you, 'What did you have for lunch or dinner on December 29th', I don’t think you will remember. If you are able to tell them, then it means you have that karma!
Certain activities and actions do not imprint an impression on the mind, in this case there is no karma.
If I ask you, 'Which movie did you watch on September 23?' And you do not remember, it means that the movie has not caused a karma on you.
Any impression which is compelling is what karma is. For example, you have a habit of drinking coffee every day, and one morning you wake up and there is no coffee available, or you decide not to drink coffee, what happens? I have heard people say that they get a headache. This is coffee karma! It is when you don’t do something and there is a reaction to it. But, you can get over that karma.
If you have a headache, instead of having coffee again, take an aspirin or drink lots of water and bear that little pain, and then in 2-3 days you will no longer have headaches. This is how you get over coffee karma.
Similarly, people who smoke, their compulsion to smoke is smoking karma, but they can say no to it. Every habit is nothing but a karma pattern. If you say no to it, then you are already getting over it.