Alice and Bob
When the interaction between two hypothetical characters is needed to explain or describe some system, they are nearly always called Alice and Bob. Alice and Bob - A and B. This duo originally started out in 1978 as a standardized way to explain cryptography. Over time, this Metasyntactic Variable duo has been adopted in explanations of mathematics, physics, quantum effects, and other arcane places, but have also been seen in fiction. They are also found in a surprising number of trope definitions.
Where more than two characters are needed, other names are used, such as Carol and Charlie. Some names have acquired standard meanings, such as Eve the Eavesdropper. Lists of these can be found in Bruce Schneier's book Applied Cryptography, and at that other wiki.
Note that the most common names are "Alice", "Bob" and "Charlie/Charley". This works for most situations.
The use of Alice and Bob is suggested in General Suggestions, but some of us (notably those who really are called Alice and/or Bob) sometimes wish a little imagination could be applied. That's where Aerith and Bob come in. Or Jim and Mary. Or Dick and Jane.
See also Those Two Guys, Greek Chorus.
Not to be confused with Alice and Kev.
Film
- Movie and TV example: Bob & Carol & Ted & Alice.
- How to Lose a Guy in 10 Days has a romantic couple of Andy Anderson and Benjamin Berry.[context?]
Literature
- In most cryptography textbooks, communications are presented as being between Alice and Bob, and must be secured from a third-party interloper named Eve (for Eavesdropper, of course!). If the problem requires the involvement of more than two parties, then Charlie and Donna may be introduced. (This is the basis for the xkcd reference listed below.) Other character names sometimes used for special purposes include Mallory (a malicious active adversary, capable of changing the messages sent between Alice and Bob, whereas Eve merely listens), Trent (a mutually trusted third party, whom Alice and Bob might prevail upon to execute protocols in which they don't trust each other), and Peggy and Victor (the prover and verifier, respectively, in zero-knowledge proofs).
- Game Theory books often use an adaptation of Alice and Bob in "Rose and Colin" (rows and columns on game theory charts), with "Larry", or "layer" thrown in for three person games.
- Game Semantics books tend to use Abelard and Eloise (for resemblance to the universal and existental quantifier symbols, which are an inverted A and a backwards E). They are also the names of a medieval logician and his lover.
- Game Theory books often use an adaptation of Alice and Bob in "Rose and Colin" (rows and columns on game theory charts), with "Larry", or "layer" thrown in for three person games.
- Alice and Bob are the names of the parents in Vernor Vinge's Rainbows End, and a government official is named Eve Mallory.
- E. R. Emmet's "Our Factory" puzzles feature "Alf", "Bert", "Charlie", and so on.
Live Action TV
- TV and Movie example: Bob & Carol & Ted & Alice.
- One of the logos at the end of The Bonnie Hunt Show (2008-2010) is for "Bob & Alice Productions".
- Bonnie's Hunt's parents are named Bob and Alice so it is either just a reference to her parents or both.
Music
- Nerdcore Rap artist MC Plus+ has a song about cryptography named "Alice and Bob".
Newspaper Comics
- Dilbert does this in a one-way fashion with "Ted the Generic Guy", who has no consistent personality and shows up whenever a generic extra is needed. Bad things tend to happen to him.
Oral Tradition
- The Story of Alice and Bob [dead link] is a humorous after-dinner speech recounting their mythology.
- A collection of quantum-computing Alice and Bob jokes.
Video Games
- Used in a very surreal Cyberspace level in World of Goo called "Alice and Bob and the Third Party," where you intercept information-goo transmitted from cosmicGrrrl! to LaconicCrusadr13.
- Used as examples for an explanation of quantum teleportation in Remember 11.
Web Comics
- Parodied in this xkcd comic.
- Alice is introduced in the opening chapter of Freak Angels. In the epilogue, she's explaining the story to a military officer named Bob.
Web Original
- Catalog Living has the imaginary Elaine and Gary.
Real Life
- Alice and Bob really are quantum- a professor at the University of Washington has used two separate remote cameras, named Alice and Bob, to test the theory of non-locality and its potential for time travel, by attempting to receive a message before it's sent. The experiment hasn't yielded results so far, but it's telling.
- In Linguistics, it's more often John and Mary.
- Named tropical storms (typhoons, hurricanes, cyclones) are based on a sequential list of given names, replaced every year, with a different list for each region. The lists will be re-used at half-dozen year intervals, but with the names of historic "worst" storms periodically retired. That'd make Hurricane Andrew the first (A) tropical storm of the North Atlantic hurricane season in his respective year. Q, U, Z are not used; a particularly bad season (such as 2005 with Dennis, Katrina, Wilma) can exhaust the entire 23-name alphabetical list, after which the Greek alphabet (Hurricane Beta...) is pressed into service. The original lists used female names as meteorologists proposed the names of their sweethearts; more recent practice has alternated gender on each successive storm (so Alex, Brenda, Charles, Diana, Elmer, Francesca... or a similar pattern).
- A similar alphabetically-sequential naming series was used circa-1883 for a string of Atlantic and Pacific Railroad stops where steam trains took on water across the Mojave Desert. The first was "Amboy", now a ghost town on the former US Route 66. followed (from west to east) with Bristol, Cadiz, Danby, Essex, Fenner, Goffs, Home, Ibis, Java, and Klinefelter. Most of these points are now abandoned.
- Similar alphabetically-sequential naming patterns have been used for versions of software; Ubuntu uses names of animals this way, while the Android OS used to use names of foodstuffs (beginning after 'B' as the base, "Cupcake", "Donut", Éclair", "Froyo", "Gingerbread", "Honeycomb", "Ice Cream Sandwich", "Jelly Bean", "KitKat", "Lollipop", "Marshmallow", "Nougat", "Oreo", "Pie", ending just before this reached 'Q').
All The Tropes
Pages with the category "Alice and Bob":
- "No. Just... No" Reaction
- A Tragedy of Impulsiveness
- Above the Influence
- Adaptation-Induced Plothole
- Adaptation Explanation Extrication
- Alice and Bob/Analysis
- Alice and Bob/Laconic
- All for Nothing
- Amnesiac Liar
- And Stay Out!
- And the Rest
- Ankle Drag
- Anti-Advice
- Bad Mood As an Excuse
- Bathroom Stall of Overheard Insults
- Bed Trick
- Belated Happy Ending
- Bilingual Backfire
- Blackmail
- Bonus Feature Failure
- Both Sides Have a Point
- Break-In Threat
- Burping Contest
- Calling Me a Logarithm
- Cartoonish Companions
- Celebrity Survivor
- Characterization Marches On
- Class Clown
- Cleaning Up Romantic Loose Ends
- Coitus Uninterruptus
- Comforting the Widow
- Complaining About Rescues They Don't Like
- Conveniently-Common Kink
- Converse with the Unconscious
- Curb Stomp Battle
- Dartboard of Hate
- Death by Adaptation
- Debt Detester
- Defiled Forever
- Delayed Reaction
- Derailing Love Interests
- Description Cut
- Did They or Didn't They?
- Dinner Deformation
- Do Wrong Right
- Don't Sneak Up On Me Like That
- Double In-Law Marriage
- Downtime Downgrade
- Dramatic Irony
- Duet Mood Dissonance
- Easily-Overheard Conversation
- Eat Dirt Cheap
- Everyone Is Satan in Hell
- Exact Eavesdropping
- All The Tropes:Example Indentation in Trope Lists
- Explain, Explain, Oh Crap
- Fake Kill Scare
- Fan-Preferred Couple
- Finish Dialogue in Unison
- Finishing Each Other's Sentences
- Foe Cooties
- Follow the Chaos
- Footsie Under the Table
- Foreshadowing
- Forgot Flanders Could Do That
- Fox News Liberal
- Freeze Frame Ending
- Friends with Benefits
- From My Own Personal Garden
- Gibberish of Love
- Girls Are Really Scared of Horror Movies
- Give Me a Reason
- Glad I Thought of It
- Going Through the Motions
- Hairpin Lockpick
- Have We Met?
- Head-Tiltingly Kinky
- Helluva Boss
- Highlighted Text
- Hilarity in Zoos
- Holding the Floor
- How Much Did You Hear?
- Hurricane of Excuses
- Hypocritical Heartwarming
- I'm Cold... So Cold...
- I'm Standing Right Here
- I Didn't Mean to Turn You On
- I Never Told You My Name
- Idiotic Partner Confession
- Ignored Expositor
- Imagine Spot
- Indulgent Fantasy Segue
- Insatiable Newlyweds
- Insult to Rocks
- Invisible Streaker
- Ironic Echo
- Jailbird of Panama
- Just Whistle
- Kids Shouldn't Watch Horror Films
- Kissing Discretion Shot
- Kissing in a Tree
- Lame Excuse
- Leaning on the Fourth Wall
- Leonine Contract
- Let Him Choose
- Like a Weasel
- Long-Distance Relationship
- Look Behind You!
- Manslaughter Provocation
- Master of the Mixed Message
- Meat Versus Veggies
- Mercy Kill
- Misplaced Sorrow
- Mobile Shrubbery
- More Hypnotizable Than He Thinks
- Multitasked Conversation
- My Favorite Shirt
- My Name Is Not Durwood
- My Sister Is Off-Limits
- My Species Doth Protest Too Much
- Nephewism
- Never Live It Down
- No, I Am Behind You
- No Sparks
- Nobody Here but Us Statues
- Nom De Mom
- Not-So-Innocent Whistle
- Not Listening to Me, Are You?
- Oblivious Guilt Slinging
- One-Book Author
- One-Dollar Retainer/Playing With
- Only Friend
- Operation: Jealousy
- Or Are You Just Happy to See Me?
- Outside Joke
- Pair the Spares
- Paranoia Gambit
- Patchwork Kids
- Phoney Call
- Pitying Perversion
- Placebo Eureka Moment
- Please Kill Me If It Satisfies You
- Ponzi
- Preemptive "Shut Up"
- Premature Aggravation
- Public Secret Message
- Questionable Consent
- Quit Your Whining
- Race For Your Love
- Rapid-Fire "No"
- Rapid-Fire Interrupting
- Removed From the Picture
- Repeat What You Just Said
- Revealing Hug
- Right Behind Me
- Right in Front of Me
- Righting Great Wrongs
- Robbing the Mob Bank
- Sabotutor
- Said Bookism
- Schrödinger's Player Character
- Selective Enforcement
- Selling the Show
- Separated by a Common Language
- Sex by Proxy
- Sexual Extortion
- Ship Mates
- Shipping
- Shut Up and Save Me
- Sibling Switch Squick
- Single-Target Sexuality
- So You Want To/Write a Film Noir
- Some Laymanning Required
- Stairs Are Faster
- Stalker Without a Crush
- Stalker with a Test Tube
- Stood Up
- Stop Drowning and Stand Up
- Strange Minds Think Alike
- All The Tropes:Style Guide/Spoilers
- Styrofoam Rocks
- Such a Phony
- Sure, Let's Go with That
- Suspiciously Specific Tense
- Sustained Misunderstanding
- Tag-Team Suicide
- Take a Picture, It'll Last Longer
- Taking the Heat
- Tastes Like Chicken
- Tell Him I'm Not Speaking to Him
- Thanks for the Mammary
- The Cat Came Back
- The Exit Is That Way
- The Matchmaker
- The Missus and the Ex
- The Tell
- The Three Trials
- The Worst Seat in the House
- This Is No Time for Knitting
- Trial Balloon Question
- Triang Relations
- Tuck and Cover
- Twin Threesome Fantasy
- Undercover As Lovers
- Unrequited Love Switcheroo
- Vehicle Vanish
- Verbal Backspace
- Visual Development
- Voiceover Letter
- Walk In, Chime In
- War Ship
- Was It Really Worth It?
- Waxing Lyrical
- What Is This, X?
- What Is This X You Speak Of?
- Where Did We Go Wrong?
- Who's on First?
- Why Are You Looking At Me Like That?
- Wounded Gazelle Gambit
- You're Cute When You're Angry
- You Know What You Did
- You Taste Delicious
- You Wouldn't Believe Me If I Told You
- Your Cheating Heart
The manually-maintained list:
- Amnesiac Liar
- Arson, Murder, and Jaywalking
- Bathroom Stall of Overheard Insults
- Belated Happy Ending
- Bilingual Backfire
- Burping Contest
- Cartoonish Companions
- The Cat Came Back
- Celebrity Survivor
- Characterization Marches On
- Class Clown
- Coitus Uninterruptus
- Conveniently-Common Kink
- Curb Stomp Battle
- Dartboard of Hate
- Death by Adaptation
- Debt Detester
- Delayed Reaction
- Derailing Love Interests
- Description Cut
- Did They or Didn't They?
- Dinner Deformation
- Don't Sneak Up On Me Like That
- Dramatic Irony
- Easily-Overheard Conversation
- Explain, Explain, Oh Crap
- Fan-Preferred Couple
- Finish Dialogue in Unison
- Finishing Each Other's Sentences
- Footsie Under the Table
- Fox News Liberal
- From My Own Personal Garden
- Glad I Thought of It
- Have We Met?
- Head-Tiltingly Kinky
- Hilarity in Zoos
- Holding the Floor
- How Much Did You Hear?
- Hurricane of Excuses
- I Didn't Mean to Turn You On
- Imagine Spot
- I'm Cold... So Cold...
- I'm Standing Right Here
- Indulgent Fantasy Segue
- Invisible Streaker
- Ironic Echo
- Jailbird of Panama
- Just Whistle
- Kids Shouldn't Watch Horror Films
- Kissing in a Tree
- Lame Excuse
- Leaning on the Fourth Wall
- Let Him Choose
- Long-Distance Relationship
- Look Behind You!
- Mobile Shrubbery
- More Hypnotizable Than He Thinks
- My Favorite Shirt
- My Name Is Not Durwood
- My Sister Is Off-Limits
- Never Live It Down
- No, I Am Behind You
- "No. Just... No" Reaction
- Not Listening to Me, Are You?
- Not-So-Innocent Whistle
- One-Book Author
- Operation: Jealousy
- Or Are You Just Happy to See Me?
- Patchwork Kids
- Placebo Eureka Moment
- Preemptive "Shut Up"
- Premature Aggravation
- Race For Your Love
- Rapid Fire Interrupting
- Rapid-Fire "No"
- Revealing Hug
- Right Behind Me
- Right in Front of Me
- Said Bookism
- Schrödinger's Player Character
- Selective Enforcement
- Selling the Show
- Separated by a Common Language
- Sibling Switch Squick
- Single-Target Sexuality
- Write a Film Noir
- Stairs Are Faster
- Stood Up
- Styrofoam Rocks
- Such a Phony
- Tag-Team Suicide
- Taking the Heat
- Tastes Like Chicken
- Thanks for the Mammary
- The Cat Came Back
- The Exit Is That Way
- The Matchmaker
- The Three Trials
- A Tragedy of Impulsiveness
- Triang Relations
- This Is No Time for Knitting
- Twin Threesome Fantasy
- Voiceover Letter
- Walk in Chime In
- War Ship
- Was It Really Worth It?
- What Is This, X?
- Where Did We Go Wrong?
- Who's on First?
- Why Are You Looking At Me Like That?
- Why Didn't You Just Say So?
- Wounded Gazelle Gambit
- You Know What You Did
- You Wouldn't Believe Me If I Told You
- Numerous Playing With pages.
- ? and more.