Krypto is also the name of a mathematical card game. It is played with a deck of 52 cards which consists of 3 each of the numbers 1 through 10, 2 each of 11 through 17, and one each of 11 through 25.

There are several variations, but the basic idea is that each player is trying to form a certain goal number (the number on a randomly-selected card visible to all players) by arranging the numbers on 5 other cards in some order, and placing mathematical operations (+, -, x, and /, and parentheses for grouping) between them, and to do it before any of the other players do.

A supporting character published by DC Comics. Krypto first appeared in Adventure Comics #210 in 1955.

Every young boy wants a dog to play with and to act as his companion, so when DC Comics decided to introduce the character of Superboy, the young version of their popular character Superman, it was a very natural progression for the Boy of Steel to have a dog. Since the original introduction of Krypto, as the dog would be called, there have actually been three different Kryptos: one pre-Crisis and two after.

The first Kripto was originally bought for Kal-El (Superman's Kryptonian name) by his father Jor-El. It soon became obvious that Jor-El was not an animal person as he used Krypto to test out the prototype of a rocket that Jor-El planned to use to send his son off planet before the planet was destroyed. The test went successfully until Krypto's rocket was struck by a passing meteor, sending it off course.

The off-course rocket eventually landed on Earth, the same planet where Kal-El's rocket had landed, though a number of years after Superboy's. Krypto tracked his master and led him back to the rocket, where Superboy learned the dog's origin.

Krypto's secret identity was Chip, Clark Kent's dog. By surrounding his eye with woodstain thereby creating a dark patch, Krypto lived a life of anonimity until he was needed as Krypto. Since these were early comics, Krypto also had a Doghouse of Solitude, where he went for peace. Located in the asteroid belt, the Doghouse was a non-descript orange lump with a sign over the door.

After the Crisis on Infinite Earths, Krypto and the better part of the Superman family were done away with, because readers wanted believable comics with flying men in spandex. Hence it was a few years before the second Krypto appeared on the scene. An acquaintance of Superman's Bibbo Bibboski rescued a puppy from from a litter than someone had attempted to drown. The only survivor, Bibbo named the little white mongrel Krypton after Superman's planet. When the person who made the collar left of the trailing N, Bibbo changed the dog's name to Krypto. This second Krypto first appeared in Adventures of Superman #501 in 1993.

Then of late Superman visited his home world through the mysterious Phantom Zone. There he became reacquainted with one of the family pets, a dog named Krypto. When Superman returned to Earth, he brought Krypto with him. Krypto gained all of the same powers of Superman when exposed to the yellow sun. This version of Krypto first appeared in Superman #167 in 2001.

Initially, Krypto resided at Clark and Lois's apartment, but he became bored and began tearing things up. And when a Kryptonian dog tears up the apartment, he really tears up the apartment. Superman took him out and Krypto helped the Last Son of Krypton to capture some criminals, but over reacted on his next adventure and was partially responsible for the death of the villain Mongul. Since then, Superman has kept him in his Fortress of Solitude though the Dog of Steel has helped his master in a number of battles including participating in the Our World At War storyline.
