Nothingness - That which is not, essentially it describes anything or situation which does not exist at this moment.
Act - An act is a conscious attempt to cause a nonexistent situation or object to come into being. An act ...
1. modifies the shape of the world,
2. arranges the means with which one desires to achieve the intended end,
3. produces the organized, instrumental complex which connects the act to the end,
and
4. is intentional.
Authenticity - The continuous process of striving to free oneself from socio-environmental influences and achieve a more desirable state of affairs. The authentic person is always striving to become, always acting.
Absurdity - One acts in order to achieve a preferred end. Authentic action involves freeing oneself from the influences of one's society and environment. Yet, when one does this, one loses the rationale for preferring one option over another. One is forced to choose between, giving up the standards one uses to make a choice (thus being authentic, free, but making a decision based on nothing) and using one's values or preferences to make an inauthentic choice (thus not being truly free). This is absurd. Life is absurd.
Responsibility - Because each human being creates his/her own existence (with the exception of birth), he/she is completely responsible for his/her existence. Humans can modify their being. Therefore they are responsible for their being.
Anguish - This is the mode of being of freedom (how freedom exists). Since decisions determine action, you must reflect on your decisions. Such reflection generally involves considering your being and non-being in relation to a set of values. Yet, since you create yourself, you have also created and chosen your values (in the sense of recognizing them as values). So, the choice continues to remain completely dependent upon yourself. You don't trust yourself to make decisions without help. But, there is nothing outside of yourself to help you make a decision. This produces anguish because you recognize the many possible consequences of your actions, that you are completely responsible for them, and yet do not trust yourself with that responsibility because you don't feel like you are in complete control of yourself.
Values - Values exist as values because you recognize them as such. Freedom is the unique foundation of values. Values have no existence apart from your decision that they are values. Values are just ideas; they have no existence on their own.
Bad Faith - Directing negation towards consciousness itself. Essentially, one is trying to lie to oneself. For example, one denies that one could be anything other than what one is. One lulls oneself into believing that one cannot change one's circumstances, that one does not have control over one's life. A person with bad faith denies that he/she is free.