The pap test checks for changes in the cells of your cervix. Those cells come in all varieties and the more abnormal the more tests they will perform after like colposcopy, biopsies, etc. HPV does show up in the results and is the leading cause of abnormal results.
I REALLY encourage everyone to have it done yearly! It's so important to women's health!
Here is a really good link to information~
http://www.4woman.gov/faq/pap.htm#pap01