2) We usually call 12 items a 'dozen'. It got derived from an old English word meaning '2 left over' after ten.
3) Number 12 have got a Mathematical significance. 12 is convenient because its multiples and divisors are convenient: 12 = 2 x 2 x 3, 3 x 4 = 2 x 6, 60 = 12 x 5, 360 = 12 x 30. It was ALMOST our base number counting system instead of ten.
4) There are 12 tribes of Israel, originating from Jacob's 12 sons (Reuben, Simeon, Levi, Judah, Dan, Naphtali, Gad, Asher, Issachar, Zebulun, Joseph and Benjamin)
5) There are Twelve Days of Christmas in the famous song: Twelve drummers drumming, Eleven pipers piping, Ten lords a-leaping, Nine ladies dancing, Eight maids a-milking, Seven swans a-swimming, Six geese a-laying, Five golden rings, Four calling birds, Three French hens, Two turtle doves and a partridge in a pear tree had a cost of $25,431.18 for all 78 items in 2012.
6) There are twelve astrological (zodiac) signs: Aries, Taurus, Gemini, Cancer, Leo, Virgo, Libra, Scorpio, Sagittarius, Capricorn, Aquarius and Pisces.
7) The twelve Lobors of Herculese included: Slay the Nemean Lion, Slay the nine-headed Lernaean Hydra, Capture the Golden Hind of Artemis, Capture the Erymanthian Boar, Clean the Augean stables in a single day, Slay the Stymphalian Birds, Capture the Cretan Bull, Steal the Mares of Diomedes, Obtain the girdle of Hippolyta, Queen of the Amazons, Obtain the cattle of the monster Geryon, Steal the apples of the Hesperides (He had the help of Atlas to pick them after Hercules had slain and Capture and bring back Cerberus.
8) Till now, total of 12 human beings have stepped on the surface of moon.
9) It is believed that 12 years of a successful marriage are rewarded with a gift of silk or fine linen.
10) The Chinese year of birth is represented by one of these 12 animals: Rat, Ox, Tiger, Rabbit, Dragon, Snake, Horse, Goat, Monkey, Rooster, Dog, and Pig.
11) 12 Celebrity deaths in 2012: Neil Armstrong (first man to walk on the moon), Arlen Specter (discovered the magic bullet that killed President Kennedy), George McGovern (politician), Andy Griffith, Larry Hagman, and Ernest Borgnine (actors), Dick Clark ('the World's oldest teenager'), Jazz legend Dave Brubeck ('Take Five'), Singers who passed include: Whitney Houston, Disco Diva Donna Summer, Etta James ('At last') , Monkee Davy Jones, and Andy Williams.
12) As per British law, When a person reaches the age of 12, he/she can buy a PET.