D – Dh

d20 system

Any gaming system, such as Dungeons and Dragons, that uses a 20-sided die to determine the level of success of any action with a chance of failure.  To determine an action’s outcome, a player rolls the die, adds any relevant modifiers to the action, then compares the total outcome with the target number of the action.  If the player’s total equals or exceeds the target number, their action is deemed successful.  A smaller total is deemed a failed action.

Daidarabotchi

Seen many times on Mighty Morphin Power Rangers as a villain creature, the 300-feet-tall Daidarabotchi, or as some call him, Daidara-bocchi, was a colossal yokai (meaning ghost, phantom or apparition) that appears in Japanese lore.  Daidarabotchi was said to be so big, his footprints created a vast majority Japan’s lakes and ponds.  It was said to be so strong, that it once weighed two of Japan’s mightiest mountains, Mount Fuji and Mount Tsukuba, to see which was heavier.

Dalek

Created by Davros on the planet Skaro, the Daleks are the enemies of Doctor Who.  With all compassion purged from them, the Daleks will often try to exterminate those alien to them.  There have been a several variations of the Daleks encountered over the years, including a god/emperor and the Cult of Skaro.  There was also a second faction of Daleks, still under the command of their creator.

Dark Age of Comics, The (1985-98)

The Dark Age of Comics is the name given to the comic book publishing era of 1985 to 1998.  While comics had already started to get a bit darker during the previous Bronze Age, the Dark Age got even darker.  Now-classic stories like The Dark Knight ReturnsWatchmen and The Killing Joke were much more mature and adult-oriented.  Characters now cursed, had sex, used guns, and even got maimed or killed.  Also, the inclusion of dystopian political concepts became commonplace.

The 1990s were a dark time at DC Comics, indeed.  Legendary heroes were damaged like never before: Superman was killed (only to be reborn), Batman had his back broken, and Green Lantern went crazy, killing off most of the Green Lantern Corps.

At the same time, the health of the comics industry took a hit and almost collapsed in 1994, when at least 19 publishers went out of business.  External market conditions in the industry were bleak, and thousands of comic book shops went out of business as a major shrinkage in both sales and the number of collectors occurred, as a lot of people moved away from the hobby.  The years 1995-1997 were very rough years for comics.  In December 1994, Marvel Comics acquired Heroes World Distribution Co. in an attempt to set themselves up to distribute their own comics, which would reduce the market share of other distributors by one third.  The change took place in July 1995, and had a ripple effect that almost wiped out the entire comics direct market.  In 1996, Diamond Comics Distributors acquired Capital City Distribution, and in 1997, Heroes World went out of business, with Marvel Comics returning to Diamond Distributors, making Diamond the “only game in town” supplying the comic book direct market.

Something had to change and fortunately it did.  In 1997, DC revitalized the Justice League of America franchise with a new take titled simply “JLA” and written by superstar writer Grant Morrison.  At the end of 1998, Marvel revitalized their line with the creation of the Marvel Knights imprint, pulling in Kevin Smith to write Daredevil (with art by Joe Quesada) and Christopher Priest’s reinvention of Black Panther for a new generation of comics readers.   The industry was pulling out of its tailspin and entering the Modern Age.

Dark Chess

A variation on standard chess, Dark Chess is a computer version in which players cannot see all the spaces on the board, but only those spaces that meet one of the following conditions:

  1. A player has a piece on that square
  2. A player can legally move a piece to that square
  3. The space is either directly in front of one of a player’s pawns, or is adjacent to a pawn in a forward diagonal position.

The object of the game is the same: to capture your opponent’s king.  Since neither player can see the whole board, there are no check or checkmate conditions. A player can freely make a move that puts his piece in check.  Also since neither player can see all of the board, draw situations from regular Western chess may not apply.  All other rules are the same as in regular chess.

Dark Helmet

The central antagonist of Mel Brooks’ Spaceballs, the 1987 spoof of Star Wars.  This comic takeoff of Darth Vader was played by Rick Moranis in the original film, and voiced by Dee Bradley Baker for the 2008-09 animated series, which aired on the G4 and Super Channel networks.

Dark Knight, The

See Batman.

Dark Shadows

Debuting in June 1966, what began as standard daytime soap opera fare about a wealthy family in Collinsport, Maine became a runaway hit almost a year later when creator Dan Curtis, facing cancellation, made the decision to add a unique element to the cast: Barnabas Collins, a 200-year-old vampire!  After the ominous character, portrayed by Jonathan Frid, appeared on screen in April 1967, the ratings skyrocketed, due mainly to after-school youths who started watching the previously adult show to see more of the monster Barnabas.  Over the course of five years, the unique series featured story arcs involving time travel, werewolves, ghosts, a human phoenix, and even a man-made creature similar to Frankenstein’s monster named “Adam”.  The popular show, which aired original episodes until its cancellation in 1971, spawned two films: House of Dark Shadows (1970) and Night of Dark Shadows (1971), both directed by Curtis, a 12-episode 1991 revival series starring Ben Cross, a 2004 reboot TV series, and a 2012 comedic theatrical film starring Johnny Depp as Barnabas.

“Dark Side of the Rainbow, The”

The audio-video synchronization of the 1939 film The Wizard of Oz and the 1973 Pink Floyd album The Dark Side of the Moon.  When timed correctly, there are many deliberate or coincidental matches between the album’s lyrics, music fluctuations and sound effects with the action of the film.  Some claim that the album can be played three times through the run of the film, and each time, different synchronizations will occur.  Others say that after The Dark Side of the Moon is played in its entirety, the next two studio albums by Pink Floyd – 1975’s Wish You Were Here and 1977’s Animals – can be played in order for many coincidences.

Dark Tower, The

“The Man in Black fled across the desert, and the gunslinger followed.”  Thus begins Stephen King’s epic series The Dark Tower, which would eventually be made up of seven novels (with an eighth subsequently published that contains a plot that would take place between the fourth and fifth novels) and spawn a graphic novel series, as well as a feature film.  The gunslinger in the tale is Roland Deschain, who is pursuing the Man in Black at the outset of the first novel.  His overall quest is to save the Dark Tower from destruction, for that event would end both his world and ours.  In his travels, he acquires allies from different time periods in American history.

Inspired by a combination of Robert Browning’s epic poem “Childe Roland to the Dark Tower Came,” J.R.R. Tolkien’s The Lord of the Rings saga, T.S. Eliot’s epic “The Waste Land,” and the classic “spaghetti Western” films of Sergio Leone, the original novel series (made up of The GunslingerThe Drawing of the ThreeThe Waste LandsWizard and Glass, [the latter-published The Wind Through the Keyhole], The Wolves of the CallaSong of Susannah, and The Dark Tower) further inspired the graphic novel series (which contains 13 volumes published between February 2007 and September 2015), the story of which intertwines with the plot of the novels.  The 2017 motion picture The Dark Tower starred Idris Elba as Roland and Matthew McConaughey as the Man in Black.

Darth

According to George Lucas, creator of the epic Star Wars film series, “Darth” is a variation of “dark,” and is used in the Star Wars universe as a title that indicating a Dark Lord of the Sith.

Darth Maul

A Sith Lord and formidable warrior in the Star Wars universe.  Appearing in Star Wars – Episode I: The Phantom MenaceDarth Maul proved to be a dangerous adversary with his double-bladed lightsaber.

Darth Vader

The central villain of the Star Wars franchise and leader of the Empire, Darth Vader was once a noble Jedi Knight before he was seduced by the Dark Side of the Force.  As a Sith Lord in service to Emperor Darth Sidious, he masterminded the disbandment of the Jedi Order.  (According to George Lucas, “Darth” is a variation of “dark,” while “Vader” means “father.”)

Data card

See Aircard.

Data transfer rate

See Bandwidth.

Dawn of the Dead

Following the events of his 1968 horror classic Night of the Living Dead, George A. Romero’s 1978 offering tells the story of an epidemic which causes the dead to rise from their graves, in search of human brains as their only sustenance. The climax takes place in a shopping mall, leading many to surmise that the tale is actually symbolic, with the message being that advertisers and the retail market have turned humans in zombie-like consumers.  Remade in 2004 by director Zack Snyder.

Dax, Curzon

A featured backstory character throughout the Star Trek: Deep Space Nine television series, the seventh host to the Dax symbiont was a bit of a dual personality: the well-known and respected Federation dignitary was also a notorious womanizer.  Hosting the Dax entity for 82 years, Curzon was one of Dax’s most enduring and distinguished hosts, and one of the most colorful. He was a close friend and mentor to Benjamin Sisko, who called him “old man,” a habit that Sisko continued when Dax became Jadzia and then Ezri.  A prominent negotiator of the Khitomer Accords in 2293. four years prior, Curzon walked out on a speech by Kang at the Korvat colony, angering Kang, but opening the door for discussion.  Curzon first met Ben Sisko at the Palios Station when Sisko was an ensign, and they served together aboard the U.S.S. Livingston. They stayed good friends for nearly two decades.  A lifelong bachelor, Curzon died in 2367 on the planet Risa, making love with a beautiful woman, making way for Jadzia to become Dax’s eighth host.

DC Comics

Founded on February 1, 1934 by publishing entrepreneur Malcolm Wheeler-Nicholson under the name of National Allied Publications, DC was formed by National’s merging with Detective Comics, Inc., as well as the affiliated All-American Publications.  Despite being officially known as “National Comics,” the comic covers carried a DC logo and as a result, the line was commonly referred to as DC Comics.  The company officially changed its name to DC Comics in 1977, under the presidency of Jenette Kahn.

National Allied Publications’ first comic was New Fun: The Big Comic Magazine #1 which was released in February 1935.  Later that year, a second title was released: New Comics #1. The size and length of New Comics #1 became the archetype for many comics afterwards, and it would eventually become the longest-running comic series of all time.  In 1938, National launched Action Comics, featuring a brand-new character from regular contributors Jerry Siegel and Joe Shuster: Superman.  Originally dismissed as “silly” by editorial, reports soon came back noting the popularity and sales increase resulting from the Superman feature.  Superman quickly became a sensation and before long, writer Bill Finger and his artist employer Bob Kane soon submitted their character Batman to appear in Detective Comics and before long, an entire Justice Society of America had been formed including properties such as The FlashGreen Lantern, The Sandman, Wonder WomanHawkman and The Spectre, to name a few, many of whom were either created or written by the prolific Gardner Fox.

During the post-WWII years, the popularity of superheroes declined almost completely, though DC and other publishers were still going strong, moving into other genres such as funny animals, romance, sci-fi, westerns and horror.  Major characters such as Batman, Wonder Woman and Superman managed to remain in publication and by the mid-1950s, the superhero was making a comeback.  Showcase #4 in 1956 introduced readers to Barry Allen, the all-new Flash, re-imagined from his Golden Age of Comics image with a sleeker design and much more science fiction in the storyline.  Characters such as The Atom, Green Lantern and the JSA – now reinvented as the Justice League of America – soon followed, and a new superhero boom was kicked off.

During this time, The Comics Code Authority also came into play, which drastically subdued the content available in the comic book medium.

With the re-invigoration of Marvel Comics in the 1960s under the leadership of Stan Lee and Jack Kirby, DC found itself a new and more potent competitor.  Marvel succeeded by breaking what had become by then generic archetypes of superheroes by introducing characters which were younger and more flawed (and thus appeared more human and appealed to a younger crowd in a more direct manner).  After falling behind Marvel in sales, DC was finally forced to adopt much of the same system which Marvel had, by introducing such young teams as the Teen Titans to compete with The XMen.

In 1985, DC Comics penned one of the first major comic book crossovers, Crisis on Infinite Earths, which incorporated almost every DC title and character ever published by the company. The series ended with multiple Earths being erased and merging into to one unified Earth. Following this, Batman, Superman and Wonder Woman were given new leases of life, thanks to John Byrne, Frank Miller, George Perez, and a whole new line of creative minds that redefined the established heroes for a new generation.

During this time, it was determined that the comic-buying audience had matured and become more sophisticated.  The direct market for comic stores opened up, allowing a wider variety of publications to be experimented with. One such experiment involved bringing in British writer Alan Moore to pen the Saga of the Swamp Thing series. Though it did not sell well, what resulted was a new style of comic book not experienced before by mainstream readers, with its literary and story-driven complexity and execution.  Before long, other British writers such as Neil Gaiman, Peter Milligan and Grant Morrison were recruited to revamp obscure properties and tell stories with an older audience in mind.  Two seminal works from DC Comics were released in 1986: Frank Miller’s The Dark Knight Returns and Alan Moore’s Watchmen that reached unprecedented levels of critical acclaim and outside media attention.

In 1993, senior editor Karen Berger created her own imprint for mature readers called Vertigo, similar to Marvel’s Epic Comics.  Using popular titles such as Animal ManSwamp ThingHellblazerThe Sandman and Shade, The Changing Man as its blueprint, alongside new creator-owned material, DC/Vertigo became a hub for intelligent and acclaimed comic books.

In 2011, after a period of declining comic sales, to revitalize the company and to de-age the characters, DC announced they were cancelling all the main titles and relaunching 52 comic lines, beginning each with Issue #1.  The relaunch came in five waves, starting with the release of Justice League # 1 on August 31, 2011.  Talon, starring Calvin Rose, was the first solo book for a character introduced in “The New 52.”  Other titles included The MovementThe Green Team and Superman Unchained.

“DC Explosion”

By the end of the 1960s, Stan Lee had led Marvel Comics to nearing industry leader DC Comics in popularity and sales, and by the mid-‘70s, Marvel had jumped to the top of the industry.  One advantage Marvel had was a larger roster of titles, so DC’s management team decided to mount a dramatic expansion, spearheaded by editor Jenette Kahn.  The publishing house added 57 titles between 1975 and 1979 (including many cancelled titles from the ‘50s and ‘60s), increased their magazine page count from 17 to 25, and upped their prices (due to the rising cost of paper and printing) from 35¢ to 50¢.

The experiment, labeled the “DC Explosion” by the comics giant, was deemed a failure.  Poor sales continued, due to several factors: poor quality of new issues, blizzards throughout the winter of 1977/78 caused distribution problems and also kept people indoors and away from comics stores, and the generally poor economy and widespread inflation of the time.  By June 1978, DC laid off much of its staff and cancelled 40% of its publishing line (including a majority of their new characters), reducing it to only 26 titles.  Some Explosion titles – including those which introduced the characters Firestorm and Black Lightning –were cancelled prior to the publication of their inaugural issues.  Some characters would live on in limited release series such as Cancelled Comic Cavalcade in order for DC to maintain the copyrights on them, and some stories were later published under other surviving titles.  Detective Comics – the source for DC Comics’ corporate name – was scheduled to be cancelled, but the decision was made to keep the iconic line by combining it into the more popular Batman Family title.  Those outside the company mockingly dubbed this trend the “DC Implosion.”

In 2011, DC’s “The New 52” campaign received some negative publicity, referring back to its 1970s expansion (and subsequent contraction).

de Troyes, Chretien

The source of many original legends to feature the character Sir Lancelot, French poet de Troyes (1130–91) was the first poet to stress romanticism in the legends of King Arthur Pendragon.  de Troyes translated Ovid’s Art of Love and a version of the Tristan legend before composing five Arthurian romances between 1170 and 1185: ErecCligèsLancelot, ou Le Chevalier à la charrette (the first piece to introduce Lancelot); Yvain, ou Le Chevalier au lion; and Perceval, ou Le Conte du Graal.  He may also have penned the non-Arthurian tale Guillaume d’Angleterre.  Publication of his tales followed the appearance in France of Wace’s Roman de Brut (1155), a translation of Geoffrey of Monmouth’s Historia regum Britanniae (c. 1136), which had introduced the Arthurian legends to Europe.  de Troyes combined Geoffrey’s legends with Robert Wace’s concept of courtly love, as well as his images of the Round Table and Excalibur, producing octosyllabic rhymed couplets that became very popular.  de Troyes was also influenced by Ulrich von Zatzighoven, who in turn was influenced by Hugh de Morville, the poet who brought the story of Arthur to Europe when he replaced King Richard I of England (known as Richard the Lionheart) as a hostage to the Austrians in 1194.  de Morville’s work influenced.  Over the next few centuries, Chrétien’s romances were imitated by other French poets, and translated and adapted frequently as the romance narrative form continued to develop.  Erec, for example, supplied some of the material for the 14th-century poem “Sir Gawayne and the Grene Knight.”  It is likely that de Troyes’ knowledge of court life emerged from his frequent presence at the court of Countess Marie, daughter of Eleanor of Aquitaine (who would later become queen to England’s King Henry II).

Deadly Duck

Released by Sirius Software Inc. at the beginning of 1982 for the Atari 2600 and Commodore VIC-20 game systems, Deadly Duck had one of the most unique premises of any video game: As a bullet-spitting duck, the player must avoid and defend himself against flying brick-dropping crabs!

Deadpool

The Marvel Comics superhero was created by artist/writer Rob Liefeld and writer Fabian Nicieza, debuting in New Mutants #98 in 1990.  Diagnosed with cancer, Canadian gun-for-hire Wade Wilson left the woman he loved for an unorthodox solution: attempting to recreate Wolverine’s healing factor through artificial means, Weapon X scientists using Wilson as their guinea pig.  Although successful, the procedure left Wilson’s skin and face terribly disfigured.  Dubbing himself “Deadpool” after the facility that created him, Wilson re-emerged as one of the world’s foremost mercenaries-for-hire.  His superhuman healing factor, which allows him to regenerate damaged or destroyed areas of his cellular structure at a rate far greater than that of an ordinary human, also gives Deadpool a virtual immunity to poisons and most drugs, as well as an enhanced resistance to diseases and an extended lifespan.  The speed at which this healing factor works varies in direct proportion to the severity of the damage.  Unlike Wolverine, Deadpool’s healing factor is mentally driven.  He is a master of assassination techniques, is an excellent marksman, and is highly skilled with bladed weapons.  He is fluent in Japanese, German and Spanish, as well as other languages.  The hero’s origin story was told in Deadpool #-1 (1997), Marvel Comics 1998 Annual Starring Deadpool and Death (1998) and Deadpool #33 (1999).  In 2016, Ryan Reynolds starred in the big-screen adaptation of Deadpool and in 2018, its sequel Deadpool 2.

Death ray

Given that Nikola Tesla’s inventions generally possessed an element of social conscience, it may seem surprising that he created a number of devices with military applications.  Nonetheless, he proposed a few instruments with strict military intentions.  After several failed proposed mechanics of war, Tesla dreamed up a new invention for the military: the death ray.

The mechanism behind Tesla’s death ray was some sort of particle accelerator.  According to Tesla, it was a byproduct of his magnifying transformer.  He promoted the device as a purely defensive weapon, designed to knock down incoming attacks.

Although it is not certain if Tesla ever succeeded in building his death ray, one often-related story says that Tesla tested the foreboding weapon in 1908.  At the time, Robert Peary was making his second attempt to reach the North Pole.  Cryptically, Tesla had notified the expedition that he would be trying to contact them.  They were to report to him the details of anything unusual they might witness on the open tundra.  On the evening of June 30, accompanied by his associate George Scherff atop Wardenclyffe tower, Tesla aimed his death ray across the Atlantic towards the Arctic, to a spot which he calculated was west of the Peary expedition, and then switched on the device.  It emitted a dim light that was barely visible, then an owl flew from its perch on the tower’s pinnacle, soaring into the path of the beam, and the bird disintegrated instantly.

Tesla watched the newspapers and sent telegrams to Peary in hopes of confirming the death ray’s effectiveness.  Nothing turned up.  The inventor was ready to admit failure when news came of a strange event in Siberia.  On June 30, a massive explosion devastated Tunguska, a remote area in the Siberian wilderness.  Five hundred thousand square acres of land had been instantly destroyed.  Equivalent to ten to fifteen megatons of TNT, the Tunguska incident is the most powerful explosion to have occurred in human history — not even subsequent thermonuclear detonations have surpassed it. The explosion was audible from 620 miles away.  Scientists believe it was caused by either a meteorite or a fragment of a comet, although no obvious impact site or mineral remnants of such an object were ever found.  Tesla had a different explanation.  It was plain to him that his death ray had overshot its intended target and destroyed Tunguska, and he was very thankful that the explosion had killed no one.  Tesla dismantled the death ray at once, deeming it too dangerous to remain in existence.  Six years later, the onset of the World War I caused Tesla to reconsider.  He wrote to President Wilson, revealing his secret death ray test.  He offered to rebuild the weapon for the War Department, to be used purely as a deterrent.  The mere threat of such destructive force, he claimed, would cause the warring nations to agree at once to establish lasting peace.  He only received a form letter thanking him for writing to the President.

Death Star

What was supposed to have been the crowning achievement of Darth Vader and the Empire in the film Star Wars – Episode IV: A New Hope, the Death Star was an ambitious project: a moon-sized control center/spaceship, from which the leaders of the Empire’s forces could attack entire planets.  Even as the Clone Wars raged, the Death Star secretly took shape in space above Geonosis.  The Empire completed construction of the Death Star, but Rebel Alliance spies managed to steal its schematics.  Their goal: to find a weakness within the superstructure and exploit it.  Darth Vader led an Imperial hunt to recover the plans. While he proved unsuccessful on that front, the Sith captured Princess Leia Organa, a suspected Rebel sympathizer.  In a display of the Death Star’s might, Grand Moff Tarkin used the space station to destroy the Princess’ home planet of Alderaan, killing billions.  With the stolen plans delivered to the Alliance, it was discovered that a proton torpedo, shot precisely into a small exhaust port, could trigger a reaction that would destroy the Death Star. The Rebels launched a desperate attack, and Luke Skywalker flew an X-wing down the Death Star’s trench, striking the port.  Though Darth Vader escaped, the dangerous space station was destroyed.

Deep Blue

International Business Machines (IBM) computer scientists had been interested in chess computing since the early 1950s.  Over the years, many computer programmers had taken on chess masters in attempts to outthink human strategy and creativity.  The computers had all lost.  Then, in 1985, a graduate student at Carnegie Mellon University, Feng-hsiung Hsu, began working on his dissertation project: a chess-playing machine he called ChipTest.  A classmate of his, Murray Campbell, collaborated on the project, and in 1989, both were hired to work at IBM Research.  There, they continued their work with the help of other computer scientists, including Joe Hoane, Jerry Brody and C. J. Tan.  The team named the project “Deep Blue.”  Garry Kasparov, the world chess champion, had beaten an earlier version of Deep Blue in 1996; a 1997 match against an updated version of the computer was billed as a “rematch.”

The match, held at the Equitable Center in New York, lasted several days and received massive media coverage around the world.  Deep Blue could explore up to 200 million possible chess positions per second.  On May 11, 1997, Deep Blue beat Kasparov after a six-game match: two wins for IBM, one for the champion, and three draws.  Game 6 ended in a crushing defeat of the champion.

Deep Blue had an impact on computing in many different industries.  It enabled researchers to explore and understand the limits of massively parallel processing.  The architecture used in Deep Blue was applied to financial modeling, including marketplace trends and risk analysis; data mining; and molecular dynamics, a valuable tool for helping to discover and develop new drugs.

Deep Blue was eventually retired to the Smithsonian Museum in Washington, DC, but IBM went on to build new kinds of massively parallel computers, such as IBM Blue Gene.  The Deep Blue project inspired a more recent grand challenge at IBM: building a computer that could beat the champions at a more complicated game: Jeopardy!

Defender

Classic side-scrolling shoot-‘em-up arcade game produced by Williams Electronics.  Unlike most games of the era, which featured at most a few buttons and a controller, Defender offered five buttons along with a joystick to perform the game’s obscure actions.  Nevertheless, Defender became a smash hit for Williams.  John Harris called Defender the “hardest significant game there is,” remarking that such a demanding game seems “unthinkable” today.

The primary goal of Defender is for the player to pilot his or her spaceship to prevent stranded Humanoids from getting abducted by enemy aliens, include the Lander, Mutant, Bomber, Pod, Baiter, and Swarmer.  To accomplish this, the Defenderwas armed with a relatively slow-to-fire, edge-of-screen-length laser, a limited number of screen-clearing smart bombs, and an unrestrained ability to randomly disappear into hyperspace — perhaps reappearing to worse danger or even immediate destruction.  Fortunately, tracking the Humanoids was simplified with an innovative scanner or “minimap” shown at the top of the screen, as well as a distinctive sound effect that played whenever a Humanoid was in danger.  Innovative in its time, the minimap feature now appears in many games.  Despite the game’s complexities, its “catch and rescue” play mechanic has been mimicked in many subsequent games.

Defrag

See Defragment.

Defragment

To reorganize fragments of related data into a contiguous arrangement, as on a disk or hard drive.  Also called “defrag.”

Dent, Harvey

In DC Comics’ Batman universe, Harvey Dent is the upstanding district attorney of Gotham City, and one of Batman’s few allies in the war against the corruption of their streets.

Deoxyribonucleic acid (DNA)

  1. Known commonly as DNA, the long macromolecule is the main component of chromosomes in all living things (except for some viruses). It is constructed of two nucleotide strands, twisted together in a ladderlike arrangement known as a “double helix.”  The 48 chromosomes of a human cell contain a total length of about 6 billion base pairs of DNA.  The sides of these strands are backbones that consist of alternating sugar and phosphate groups, and the rungs of which are hydrogen-based complementary bases.  DNA is formed by linking the nucleotides together in a chain, with bonds between the sugar and phosphate groups of adjacent nucleotides, and a base attached to each sugar as a side chain.  The four bases are two purines (adenine and guanine), and two pyrimidines (cytosine and thymine).

DNA carries the cell’s genetic information and hereditary characteristics, and performs three important functions:

  • When a cell divides (via a process known as mitosis), the DNA uncoils, and each strand creates a new partner from the surrounding material in a process called replication.  The two cells that result from this cell division have the same DNA as the original.  See Mitosis.
  • In sexual reproduction, each parent contributes one of the two strands in the DNA of the offspring.
  • Inside the cell, the DNA governs the production of proteins and other molecules essential to the cell.

DNA was discovered in 1869, but its role in genetic inheritance was not demonstrated until 1943.  The structure of DNA was first described as a double-helix polymer (a spiral consisting of two strands wound around each other) by J. D. Watson and F. H. C. Crick in 1953.

2. The set of nongenetic traits, qualities or features that characterize a person or other living thing.

Desktop

  1. Literally, the workspace on a user’s desk.
  2. A type of computer, including a central processing unit (CPU) and a monitor, which is compact enough to fit on a user’s desktop.
  3. The desktop is the primary user interface of a computer, also known as the main screen. The desktop typically includes the desktop background (or wallpaper) and icons of files and folders you may have saved to the desktop.

Destiny

A moon orbiting the border world New Melbourne, the second planet in the Red Sun system of “The ‘Verse,” the semi-fictional universe created by Joss Whedon for his television series Firefly and its follow-up motion picture Serenity.  Mysteriously, it is listed as “quarantined by The Alliance” in the Core Book to Firefly: The Role-Playing Game.

Dhampir

One who has been infected by a vampire, but not turned, thus creating a human/vampire hybrid.

Also called a “daywalker,” a dhampir (a word originating in the language of Slavic gypsies) is believed to be a child of a vampire father and a human mother.  Traditionally, a dhampir has the powers of a vampire (but what those powers are depend on the vampire and the myth), but none of the usual weaknesses.  How a dhampir is made is also debated on, but a common belief is that it is the child of a human mother who has been bitten by a vampire while pregnant.  In pop culture, one well-known dhampir is Marvel Comics’ character Blade.

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