One word that has echoed the Copenhagen summit going on now has been "binding".
But what does it mean?
Binding is anything that is executed with proper legal authority, thus the example a "binding contract".
So many leaders are talking about a legally binding climate change agreement and a politically binding one at the same time.
Countries like Russia are pushing for a comprehensive binding agreement, which means that the agreement should include all countries.
If a document is legally binding, violation of the terms implies in penalties for those who break the contract, making the document void.
Which do you think is more binding - a handshake or a signature?
Here is one the chief blogs on the summit.