What is gamma correction in image processing

img.nobor{border:none;-moz-box-shadow: none;-webkit-box-shadow: none;box-shadow: none;-moz-border-radius: 0;-webkit-border-radius: 0;border-radius: 0;}



What is gamma and gamma-correction? What is it for? Why should I care about it?

These are the questions you may have already met, if you once made an offer to obtain the correct graphics display, as a simplest example - on your own monitor.