Well, both have lots of legs, but actually there are many differences between the two. And one can have a nasty bite, so don't mix them up! Both centipedes and millipedes belong to the subgroup of multilegged creatures called myriapods.
The cute little creature above is a Millipede. It does not bite, it does not sting, and rolls into a little coil when threatened.
Millipedes belong to a separate class of diplopods. There are about 12,000 species of millipedes. The class name is also from the Greek, diplopoda which means "double foot." Although the word "millipede" derives from the Latin for "thousand feet," no known species has 1,000 feet, the record holds at 750 legs. er, newsflash from the end of 2021: A newfound species of millipede has more legs than any other creature on the planet—a mind-boggling 1,300 of them.
Characteristic Centipede Millipede
Antennae Long Short
Number of legs One pair per body segment Two pairs per body segment
Appearance of legs Visibly extend from sides of body Do not visibly extend from body
Movement Fast runners Slow walkers
Bite Can bite Does not bite
Injects venom to paralyse prey Curls body into tight spirals
Centipedes The creature below is a centipede. They have a really nasty "bite" that really, really hurts.
Within the myriapods, the centipedes belong to their own class, called chilopods. There are 8,000 species.
The class name originates from the Greek cheilos, meaning "lip," and poda, meaning "foot." The word "centipede" comes from the Latin prefix centi-, meaning "hundred," and pedis, meaning "foot." Despite the name, centipedes can have a varying number of legs, and no species has only 100 legs like the name suggests.
Our Hong Kong Centipede, the Scolopendra which is pictured above, is the largest and therefore the most dangerous centipede. Interestingly, this genus is characterised by 21 pairs of legs (ie 42 and not 100). The last pair of "legs" as shown on the far left of the photo are not used for locomotion but is a sensorial organ.