Why are huggies diapers so absorbent?

Huggies diapers, like most types of diapers, contain a special kind of crystal in the lining (under many layers of cotton of course). These tiny crystals--usually used are polyacrylamides crystals--are made up of superabsorbent polymers that basically absorb extremely large amounts of fluid (i.e. urine) and then swell up and retain the liquid.