Acne scars are formed as part of the body’s natural healing process, as it heals inflamed acne. Most acne scars are depressed scars that appear in three forms: Icepick scars, Boxcar scars and Rolling scars. The Icepick scars look like deep narrow holes and may extend deeper in the tissue. Other types of scars are Boxcar scars which are round depressions with steep sides that look like large pores. Finally, Rolling acne scars cause undulations that look like rolling waves. Another category of acne scars is raised scars that usually become less noticeable over time unless they develop as keloids that are thick and rubbery scars that can grow beyond their original borders.