I don't get crotchless panties

So, I had to have crotchless panties explained to me by a MALE friend today. I am 26, female, and have never really owned lingerie in my life. Perhaps its the pain in the face due to the dentist appointment, or the vicodin running through my system but, I really, truly, could not wrap my head around how these panties worked. I kept imagining the panties just flapping in the breeze at front and back and just not looking cute at all. I have been browsing Fredericks, debating getting some lingerie. And these http://www.fredericks.com/Wide_Lace_Crotchless_Panty/91405,default,pd.html?cgid=sa2 are very cute. But I didn't understand how it worked. I get it now. Maybe I'll even get some someday. But, I really didn't understand until 2 minutes ago.

-Newt.