Hannah was a woman that was mostly eaten before she turned into a zombie. With most of her body gone, she simply lies on the side of the road next to a bicycle that was presumably hers.
Written by Robert Kirkman and drawn by Tony Moore.
Due to being an immobile zombie, Hannah lies where she was eaten. When Rick Grimes finds her bicycle, all she can do is snarl at him. Once Rick is equipped for his drive to Atlanta, he stops by Hannah and puts a bullet in her head.
Hannah makes her appearance as the "bicycle girl zombie" in the first episode of AMC's version of the comic. She is played by Lillie Birdsell. The show has Hannah missing her lower half of her body instead of just being picked clean. She is also able to crawl. Rick finds her by following her entrails through a park before leaving for Atlanta and puts a bullet in her head.
She isn't named until a series of webisodes is released that tells her story for the show. She's a divorcee with two kids (whose fates are unknown). She takes an axe to her former husband's now-zombie wife before fleeing the house with her kids and then getting eaten. Being eaten in the middle of the street, it seems her placement by a bicycle is more happenstance than the comic suggests.
The six-part web-series "The Walking Dead: Torn Apart" was originally aired on AMC's official website in October, 2011 to promote the start of the second season a few weeks later.