One must not oversimplify action and inaction by thinking that the former means the activity of the body and the latter its idleness. The definition of these three terms is as under:
Action: That which is prescribed in the scriptures and not merely approved by men.
Forbidden action: That which is forbidden by the scriptures.
Inaction: Renunciation of action.
Activity is the very essence of life. The great Seers of ancient days evaluated the life on the basis of the quality of activities. This is explained in the following chart.

Life is constituted of moments of activity and inactivity. Through inactivity neither progress nor deterioration is ever possible. Periods of activity alone create man. Such creation of man depends upon what type of activity he undertakes. Activity or Karma need not imply only ritualism but it encompasses all dedicated actions. It is known to all that action means movement of the body etc., and inaction means absence of such movements or to sit quiet. But these two terms imply much more than these familiar ideas.

Activity can be broadly classified as constructive and destructive. Constructive activities are termed here as Karma (i.e. actions to be done) which contribute towards the evolution of an individual. Destructive activities are those which debase the individual and hence totally condemned by the Sastras; these are referred to here as Vikarma (actions to be avoided).

Karma (Constructive activity) can be of three types:
Nitya Karma: constant duties
Naimittika Karma: special duties on special occasions and
Kamya Karma: duties done expecting rewards.

Sri Krishna advises Arjuna to avoid prohibited actions (Vikarma) and to pursue the constructive and creative activities of self-development (Karma) and to totally reject inactivity (Akarma). It is essential that a true seeker should know the triple classification of activities constituting life. Sri Bhagavan admits that it is not easy to understand these concepts of activities implying that for evaluating actions one should go beyond the actions as such and look into the motive or desire or intention behind such actions. If motives are pure actions will be noble and if motives are impure so also actions will be mean.

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Hi, for; there is something boddhavyam, to be known; api, even; karmanah, about action enjoined by the scriptures; and there is certainly something to be known vikarmanah, about prohibited action; so, also, there is something to be known akarmanah, about inaction, about sitting quietly. (The words ‘there is’ are to be supplied in all the three cases.) Because gatih, the true nature, i. e. the essential nature; karmanah, of action-implying karma etc., viz action, prohibited action and inaction; is gahana, inscrutable, hard to understand.

‘What, again, is the essential nature of action etc. which has to be understood, and about which it was promised, “I shall tell you….” (16)?’ This is being stated: