The way the application works is you record yourself "singing" the song, add certain tags or hints to the recording of how you remember the song and someone else will listen to your recording, and if they recognize the song, they will post a suggestion (also known as a response) to your request.
The tags or hints will help whoever is listening to your recording recognize the song. In addition to the tags, you'll also be able to enter the last time and place you heard the song.
Since the application is community driven, anyone can like or dislike posts (requests or responses) to reflect the posts' accuracy. For instance, one can downvote a request if it were recorded poorly or upvote a response if it were the actual identified song. The more people upvoted a response, the more likely it turned out to be the actual identified song.