What makes a classic a classic?

[SophSoph]

Right, im pretty new to this but i have a real passion for english and have taken up a project regarding classic literature novels and i want to get your opinions on the subject. What makes a classic a classic? who decides this? and general opinions on whether or not you think classic books are relevent in todays society? Thank you :)

[cafolini]

The marketting and the people make the value of a book. But I don't think classics as such will ever come back to the avantgarde. They are too simple or rather all-encompassing for the postmodern world of today. They just have historical value. Most of their subjects do not apply to the evolutionary needs of the common man.