The simplest explanation is that karma is one’s total spiritual inheritance.
It includes both the linear and the nonlinear; both the known and the unknown. Just by being born as a human being is in itself the expression of many millions of factors. The physical expression of it – your body, is determined by genes or chromosomes, in itself part of your karma.

We are all born with a calibratable Level of Consciousness LOC). In the Western world, we call karma the destiny of the soul. At the same time, the Eastern world interprets karma as a continuing evolution of the spirit over great expanses of time. Karma and its associated Level of Consciousness reflect every action, no matter how small, and every intention no matter how weak. All is recorded in the infinite Level of Consciousness.

Dr David R Hawkins and Lord Byron Poetry About Karma.

It’s been confirmed that we are all accountable to the mind of God, or as some prefer to call it Divine Providence, or just the Universe. Everything we do is etched for eternity. A responsibility that cannot be overestimated.