IT -  The disembodied brain that controls all the inhabitants of Camazotz with its revolting, pulsing rhythm. IT, identified with the Black Thing, is the embodiment of evil on this planet.
The Black Thing  -  A cold and dark shadow that symbolizes the evil forces that Meg, Calvin, and Charles Wallace must fight against in order to rescue their father.
Mrs. Whatsit -  The youngest of the three celestial beings who accompany the children on their adventure. Meg initially comes to know Mrs. Whatsit as the tramp who stole bed-sheets from their neighbors and then sought shelter from a storm in the Murrys' warm kitchen. She later learns that Mrs. Whatsit gave up her existence as a star in order to fight the Dark Thing.
Mrs. Which -  The oldest of the three celestial beings who accompany the children on their adventure. Mrs. Which has difficulty materializing and is usually just a shimmering gleam. Her unconventional speech is usually rendered in capitalized words, with the first consonants repeated several times.
Mrs. Who -  The second of the three celestial beings who accompany the children on their adventure. She usually speaks in quotations from famous thinkers and writers because she finds it too difficult to craft her own sentences. When the children first meet Mrs. Who, she is sewing sheets in the haunted house in their neighborhood.
Mr. Murry  -  Meg's father and a physicist who works for a top-secret government agency on experiments with travel through space-time in the fifth dimension. In trying to tesser to Mars (i.e., travel through a tesseract, or wrinkle in time), he is captured and imprisoned on the dark planet of Camazotz. When the plot begins, no one on Earth has heard from him for over a year.
Aunt Beast -  This tall, furry, many-tentacled inhabitant of the planet Ixchel cares lovingly for Meg after she is nearly destroyed by the Black Thing. Aunt Beast, like all the creatures on Ixchel, lacks eyes and has no concept of light or vision.
Happy Medium -  A jolly, clairvoyant woman in a silk turban and satin gown who shows the children a vision of Earth through her crystal ball. The Medium is reluctant to show them anything unpleasant, but the Mrs. W's insist that they see what they are up against.
Man with the Red Eyes  -  A robot-like inhabitant of Camazotz who tries to hypnotize Meg, Charles Wallace, and Calvin in the CENTRAL Central Intelligence building. The Man, like all of Camazotz, is totally controlled by the power of IT.
Mrs. Murry  -  Meg's mother and an experimental biologist who works out of a lab in the Murry home. She is at once a brilliant scientist and a loving mother who cooks meals for her family on her Bunsen burner. She also writes loving letters to her absent husband every night.
Mr. Jenkins -  Meg's cold and unfeeling high-school principal who calls her "belligerent and uncooperative" and implies that her family is in denial about Mr. Murry's true whereabouts.
Mrs. Buncombe -  The wife of the constable in Meg's hometown, who has twelve bed-sheets stolen from her at the beginning of the novel.
Sandy and Dennys Murry  -  Meg's athletic and socially successful ten-year-old twin brothers who encourage her to let them fight off the bullies who make fun of Charles Wallace. The twins do not accompany Meg and Charles Wallace on their interplanetary adventure.
Calibre
A calibre (or caliber in American English) is the diameter of the barrel of a gun. For example, a rifle with a diameter of 0.22 inch is a .22 cal. Guns that have a particular calibre are designed to fit and use bullets of the same calibre.
Callibre is measured in inches, not millimetres. Common callibres include:
Sandro Rosell
Alexandre Rosell i Feli or Sandro Rosell (born March 6, 1964 in Barcelona) is the current chairman of FC Barcelona. He was the vice-president from 2003 to 2005.
Bitterness
Bitter, one of the five basic tastes.
Common bitter foods and beverages are the coffee, pure chocolate, beer, citrus peel and escarole. Quinine is also known for its bitter taste and is found in tonic water.
Comet Shoemaker–Levy 9
Comet Shoemaker-Levy 9 was a comet. It broke apart and crashed into Jupiter, in July 1994. The event was special because people could see, for the first time, how objects in the Solar System, outside Earth, collided. It caused a large amount of coverage in the media. The comet was carefully watched by astronomers worldwide. The crash gave new information about Jupiter. It also showed up its role in reducing space debris in the inner Solar System. The name came out of the discovers' last names.
The comet was discovered by astronomers Carolyn and Eugene M. Shoemaker and David Levy on March 24, 1993. It was found in a picture taken by the Schmidt telescope at the Palomar Observatory, in California. When it was discovered, it was orbiting Jupiter. It was the first comet seen to be orbiting a planet. Scientists think that it had been orbiting the planet for 20 - 30 years before its discovery.
Calculations showed that its unusual broken up form was due to a previous closer approach to Jupiter in July 1992. At that time, the orbit of Shoemaker-Levy 9 passed within Jupiter's Roche limit. Jupiter's tidal forces had acted to pull the comet apart. The comet was later observed as a series of pieces up to in diameter. These fragments collided with Jupiter's southern hemisphere between July 16 and July 22, 1994. The pieces were moving at a speed of approximately 60 km/s. The impact scars were more easily seen than the Great Red Spot and they stayed for many months.
International League
The International League (IL) is a minor league baseball league based in the Eastern United States. Like the Pacific Coast League and the Mexican League, the International League plays at the Triple-A level. It was so-named because it had teams in both the United States, Canada, and Cuba. However, all of the league's teams are now based in the U.S.
Cigerxwîn
Cigerxwîn or Cegerxwîn ("pronounced Jigar Khwin") (1903 - October 1984) was a renowned Kurdish polymath, and nationalist.
Division by two
In mathematics, division by two is when a number is divided by two. Some cultures, like the ancient Egyptians, thought this was a different operation than division. Some mathematicians up until the 16th century (1500-1599) thought this too. Today division by two is handled specially in modern computer programming.
Division by two is also called halving, mediation, and dimidiation.
In a binary number system, there are only two digits: 0 and 1. All other numbers are represented with those two digits. For example, "one" is 1, "two" is 10, "three" is 11, "four" is 100, and so on. Most of the time people use a number system with ten digits (the numbers 0 through 9.) This is called the decimal number system.
Division by two in binary is very easy. It is done by dropping the last digit on the right of the number. This is called a "bit shift operation." For example, if we performed a bit shift operation on the binary number 100, we'd get 10. Since binary 100 is decimal 4, and binary 10 is decimal 2, this makes sense.
Another example is performing a bit shift operation on 1101. This would leave us with 110, but we dropped a 1 from the end, not a zero. This also makes sense because 1101 in binary is 13 in decimal. If we divide 13 by 2, we get 6 with a remainder of 1 (we have 1 left over.)
Computers use the binary number system to store information. Information is broken up into tiny pieces called "bits". Each bit is either a 0 or a 1. Because of this, the fastest and easiest way for a computer to do division is by a bit shift operations -- division by two. Replacing regular division with bit shifts is a way to do program optimization. (Program optimization is trying to make a program faster and more efficient.)