This particular TED talk discussed the reality of perception in our society and the importance of having the right mentality when facing certain tasks.
Body language affects how others see us, but it may also change how we see ourselves. Social psychologist Amy Cuddy shows how “power posing” — standing in a posture of confidence, even when we don’t feel confident — can affect testosterone and cortisol levels in the brain, and might even have an impact on our chances for success.
So, when you are going for your next interview, think about your posture, how that reflects how you are feeling and what your prospective employer is seeing. This applies to many other instances of course.