What's a nonbinding resolution?

A nonbinding resolution such as the one being debated on Iraq does not have the force of law.

There are three kinds of congressional resolutions: simple, concurrent and joint. Simple resolutions, approved by only one chamber, and concurrent resolutions, by both chambers, often express non-statutory opinion or concern the internal operations of Congress and are usually nonbinding. One exception is concurrent resolutions on the budget, which in principle are binding, requiring both houses to adopt certain budget blueprints.

Joint resolutions generally are binding in that they are sent to the president for his signature and have the force of law. Authorizations of the use of military force are binding joint resolutions. So are constitutional amendments, though instead of going to the president for his approval, they are sent to the states for ratification.