What is a gift exchange party?

Could you please explain what a gift exchange party entails? I'm curious about the concept and how it differs from a traditional gift-giving occasion. Do participants bring gifts to exchange with each other, or is there a specific process or theme involved? I'm also interested in knowing if there are any rules or guidelines that typically govern such events. Lastly, are gift exchange parties a common practice in various cultures or are they more specific to certain regions or communities?