Guest reviews are reviews that you post about your guest to give them feedback on their stay - their behavior, the state in which they left the property, etc.
Host reviews are reviews that your guest posts about you to give you feedback on their stay - the level of maintenance of the property, your ability to answer questions and provide assistance, etc.
We recommend always encouraging your guests to provide you with feedback and a review. Posting mutual reviews can help you become better guests and hosts, respectively. A lack of reviews can lead to a low Airbnb ranking and the eventual pausing of the listing.