explain xkcd - User contributions [en]

1759: British Map

2016-11-14T15:44:20Z

Wargames: /* Explanation */

{{comic
| number = 1759
| date = November 14, 2016
| title = British Map
| image = british_map.png
| titletext = West Norsussex is east of East Norwessex, but they're both far north of Middlesex and West Norwex.
}}

==Explanation==
{{incomplete|Started the table, editing it now.}}

Many areas of the UK are most familiar to foreigners thanks to their depiction in various fantasy novels and TV series. This map labels some of these, as well as including many silly names that simply sound like real British towns to an American ear. A protractor is shown off the coast of the {{w|Mull of Kintyre}} in reference to the "{{w|Mull of Kintyre test}}" - the angle of the Mull defines the maximum allowed erectness for a man on British television.

{| border =1 width=100% cellpadding=5 class="wikitable sortable"
|'''Label on the map''' || '''Explanation''' || '''Actual location''' || '''Notes'''
|-
| Helcaraxë
|| The "[http://lotr.wikia.com/wiki/Helcarax%C3%AB Grinding Ice]", an area of {{w|Middle-Earth}}. Like Helcaraxë, northern Scotland is cold, mountainous and in many areas inhospitable.
|| The {{w|Grampian}} region
||
|-
| Blick
|| ?
|| ?
||
|-
| Everdeen
|| {{w|Katniss Everdeen}} is the heroine of ''{{w|The Hunger Games}}'' series of novels and films
|| {{w|Aberdeen}}
|| In colloquial Scots, its pronunciation is very similar to "Everdeen."
|-
| Highlands
|| {{w|Scottish Highlands|No joke}}
|| {{w|Scottish Lowlands}}
|| Maybe deliberate trolling - Scots have strong feelings about where the Highland-Lowland border is
|-
| Norther Sea
|| Pun on the {{w|North Sea}}
|| {{w|Sea of the Hebrides}}
||
|-
| Nothingham
|| Pun on {{w|Nottingham}}
|| Slightly further North
||
|-
| Loch Lomond

|| {{w|Loch Lomond|No joke}}

|| Loch Lomond is the largest lake in the UK, and the subject of a well-known {{w|The_Bonnie_Banks_o%27_Loch_Lomond|traditional song}}.
|-
| Fjordham
|| {{w|Fjords}} are glacial valleys. "-ham" is a common English placename suffix from Old English, related to the modern {{w|Hamlet (place)|hamlet}}. There are several villages in England named {{w|Fordham}}.
|| Near {{w|Oban}} on the {{w|Firth of Lorn}}
|| The Scottish word "Firth" is related to "Fjord", although Lorn is not a fjord in the strict scientific sense - it was formed along the {{w|Great Glen Fault}} by tectonics, rather than glaciers
|-
| Glassdoor
|| {{w|Glassdoor}} is a website where employees can review their employers
|| {{w|Stirling}}
|| Although it's shown near Stirling, the reference seems to be to {{w|Glasgow}}
|-
| GMT
|| A reference to {{w|Greenwich Mean Time}}. Shown on the map near the London district of Greenwich through which the GMT meridian passes.
||
||
|-
| Eavestrough
|| A dialectal word for {{w|rain gutter}}
|| {{w|Edinburgh}}
||
|-
| Seasedge
|| Procan's realm in ''Dungeons & Dragons''
|| Somewhere near the Scotland-England border
||
|-
| Chough
|| A {{w|Chough|species of bird in the crow family}}
|| The {{w|Scottish Borders}}
||
|-
| Meowth
|| {{w|Meowth}} is a cat-like Pokémon
|| {{w|Ayr}}
||
|-
| Glutenfree
|| {{w|Gluten-free}} food lacks the protein {{w|gluten}}. This allows {{w|coeliac disease}} sufferers to enjoy it, but has also become a dietary fad in itself.
|| {{w|Cairnryan}}, {{w|Dumfries and Galloway}}
||
|-
| Blighton
|| A pun on {{w|Brighton}}
|| The {{w|Scottish Borders}}
|| The real Brighton is much further south, on the south coast.
|-
| Eyemouth
|| {{w|Eyemouth|Not a joke}}
|| near {{w|Newcastle-upon-Tyne}}
|| The real Eyemouth is further north, where "Seasedge" is marked on the map.
|-
| Earhand
|| A pun on Eyemouth
|| {{w|Carlisle}}
||
|-
| Hairskull
|| A pun on Eyemouth
|| {{w|Teesside}}
||
|-
| Belfast DeVoe
|| {{w|Belfast}}, capital of Northern Ireland, mashed up with the rock band {{w|Bell Biv DeVoe}}
|| {{w|Belfast}}
||
|-
| Lakebottom
|| The {{w|Lake District}}. "-bottom" is a common placename across Northern England, and refers to a town in a valley.
|| {{w|Lake District}}
|| Below Lakebottom is a sketch of lake with yachts on it. This is {{w|Windermere}}, the largest lake in England, where many boating speed records were set.
|-
| Braintree
|| {{w|Braintree, Essex|Not a joke}}
|| {{w|North Yorkshire}}
|| The real Braintree is much further south, near where "Paulblart" is on the map.
|-
| Skinflower
|| A pun on Braintree
|| {{w|Yorkshire Dales}}
||
|-
| Bjork
|| {{w|Björk}} is an Icelandic singer
|| {{w|East Riding of Yorkshire}}
|| The reference is presumably to York, although it's a bit too far east.
|-
| Weedle
|| {{w|Weedle}} is a Pokémon, and also a word meaning "to obtain by trickery or persuasion"
|| {{w|Forest of Bowland}}
||
|-
| Eeugh
|| An expression of disgust
|| {{w|Kingston-upon-Hull}} (generally just "Hull")
||
|-
| Crewneck
|| A shirt with a {{w|Crewneck|simple round collar}}.
|| {{w|Blackpool}}
||
|-
| Paisley
|| {{w|Paisley, Renfrewshire|No joke}}. It sounds funny to Americans because it's associated with {{w|Paisley (design)|paisley}} fabric, a Persian-style print invented in the town
|| {{w|Burnley}}
|| The real Paisley is in Scotland, near Glasgow.
|-
| Basil
|| {{w|Basil|A herb}}, and {{w|Basil Fawlty|one of the most famous British TV characters}}.
|| {{w|Scunthorpe}}
||
|-
| Aidenn
|| An apparent pun on the {{w|Scouse}} accent: {{w|h-dropping}} and {{w|th-fronting}} mean the common "hey, then" would be pronounced "ai denn".
|| {{w|Merseyside}}
||
|-
| Hillfolk
|| {{w|Hillfolk}} is an RPG game. "-hill" (referring to, well, a hill) and "-folk" (referring to a tribe or culture) are common in British placenames
|| {{w|Manchester}}
|| Manchester's name does in fact reference hills: it means "castle on the {{w|breast-shaped hill}}"
|-
| Waterdown
|| To "water something down" is to weaken it. "-down" is common in British placenames and refers to {{w|Downland|chalk hills}}.
|| Near {{w|Grimsby}}
||
|-
| Dubstep
|| {{w|Dubstep}} is a genre of electronic music with a heavy bass line.
|| {{w|Dublin}}
|| Dublin is the only non-UK settlement in the map, and one of two on the island of Ireland.
|-
| Borough-upon-Mappe
|| By being recorded here, this is literally a borough upon a map. The "-upon-" is a common element of placenames for towns on rivers, although there's no River Mappe.
|| {{w|Lincolnshire Wolds}}
||
|-
| Fhqwhgads
|| "[http://www.hrwiki.org/wiki/Fhqwhgads Fhqwhgads]" is a joke from the Homestar Runner internet cartoon.
|| {{w|Crewe}}
|| This is near to the Welsh border; Welsh names often look like a mish-mash of consonants to English speakers.
|-
| Cadbury
|| {{w|Cadbury}} is a British chocolate company
|| Near {{w|Boston, Lincolnshire}}
|| Cadbury actually built a town for its workers... but it's called {{w|Bournville}}. There are several towns called "Cadbury" in the UK (where the Cadbury family presumably got its name), but none are near here.
|-
| Cabinetry
|| The art of making {{w|cabinets}}.
|| Near {{w|Oswestry}}
||
|-
| The Shire
|| {{w|Shire (Middle-earth)|The Shire}} is home to the {{w|Hobbits}} in {{w|Middle-Earth}}
|| {{w|Midlands}}
|| Tolkien drew inspiration for the Shire from the {{w|West Midlands (region)|West Midlands}}, although Tolkien was from the southern part of the Midlands (roughly where Dampshire is on the map)
|-
| Landmouth
|| Literal description
|| {{w|The Wash}}
||
|-
| Brandon
|| {{w|Brandon#United Kingdom|Not a joke}}
|| {{w|The Fens}}
|| There are several Brandons in the UK, none on the banks of the Wash. The area shown is borderline-uninhabitable, as it is marshland and lies mostly below sea-level. Only a few farms and isolated hamlets exist here.
|-
| Hamwich
|| A ham sandwich. Both "-ham" and "-wich" are common generic placenames.
|| {{w|Norwich}}
||
|-
| West Norsussex
|| Mash-up of {{w|Sussex}} ("South Saxons") with the obsolete {{w|Wessex}} ("West Saxons") and never extant {{w|Norsex}} ("North Saxons")
|| {{w|Midlands}}
||
|-
| Redsox
|| The {{w|Boston Red Sox}} are a baseball team
|| {{w|The Fens}}
|| This is not far from the British {{w|Boston, Lincolnshire|Boston}}
|-
| Keebler
|| The {{w|Keebler Elves}} advertise cookies in the US
|| {{w|Thetford Forest}}
||
|-
| Bloughshire
|| Most British counties have "-shire" in their name. Originally it meant they were administered by a {{w|sheriff}}. However, it is rare in Wales.
|| {{w|Powys}}
||
|-
| Lionsgate
|| {{w|Lionsgate|A film studio}}
|| {{w|Leicester}}
||
|-
| Kingsbottom
|| Another "-bottom". A possible reference to {{w|King's Landing}}, the capital of the Seven Kingdoms of {{w|Westeros}}.
|| {{w|Suffolk Coast National Nature Reserve|Suffolk Coast}}
||
|-
| Aberforth
|| {{w|Aberforth Dumbledore}} is {{w|Albus Dumbledore}}'s brother in the ''Harry Potter'' series. "Aber-" and "-forth" both indicate a "river mouth". "Aber-" is widespread in Wales.
|| {{w|Aberystwyth}}
||
|-
| South Norwessex
|| Another mash-up of {{w|Sussex}} ("South Saxons") with the obsolete {{w|Wessex}} ("West Saxons") and never extant {{w|Norsex}} ("North Saxons")
|| {{w|Birmingham}}
||
|-
| Dryford
|| Would refer to a river crossing without water. "{{w|Ford (crossing)|-ford}}" is a common placename element.
|| {{w|Shropshire Hills}}
||
|-
| Frampton
|| There are many {{w|Frampton}}s in the UK. It means "town on the river Frome" - and there are also several {{w|River Frome}}s. The name is famous thanks to rock musician {{w|Peter Frampton}}
|| {{w|Bury St Edmunds}}
||
|-
| Dampshire
|| A pun on the county of {{w|Hampshire}}. Generically a joking reference to any county, particularly of the {{w|West Country}}, to imply it is particularly prone to rain.
|| Gloucestershire
||
|-
| Efrafa
|| Efrafa is a rabbit warren in the story {{w|Watership Down}}.
|| {{w|Chidden}}
||
|}

{| border =1 width=100% cellpadding=5 class="wikitable sortable"
|-
! X !! Y !! Label
|-
| 258 || 32 || Helcaraxë
|-
| 244 || 55 || Blick
|-
| 294 || 80 || Everdeen
|-
| 34 || 89 || Norther Sea
|-
| 238 || 119 || Highlands
|-
| 144 || 151 || Lock Lomond
|-
| 83 || 172 || Fjordham
|-
| 440 || 184 || A British Map Labeled by an American
|-
| 164 || 192 || Glassdoor
|-
| 250 || 219 || Eavestroughs
|-
| 312 || 237 || Seasedge
|-
| 260 || 262 || Chough
|-
| 148 || 267 || Meowth
|-
| 76 || 298 || (A picture of an upsidedown protractor)
|-
| 256 || 303 || Blighton
|-
| 344 || 309 || Eyemouth
|-
| 124 || 320 || Glutenfree
|-
| 486 || 320 || North Sea
|-
| 254 || 329 || Earhand
|-
| 353 || 347 || Hairskull
|-
| 38 || 362 || Belfast DeVoe
|-
| 224 || 365 || Lakebottom
|-
| 411 || 389 || Braintree
|-
| 335 || 408 || Skinflower
|-
| 430 || 431 || Bjork
|-
| 279 || 432 || Weedle
|-
| 440 || 451 || Eeugh
|-
| 258 || 453 || Crewneck
|-
| 310 || 454 || Paisley
|-
| 414 || 473 || Basil
|-
| 259 || 479 || Aidenn
|-
| 461 || 496 || Waterdown
|-
| 288 || 499 || Hillfolk
|-
| 31 || 509 || Dubstep
|-
| 464 || 517 || Borough-Upon-Mappe
|-
| 269 || 535 || Fhqwhgads
|-
| 490 || 537 || Landmouth
|-
| 461 || 539 || Cadbury
|-
| 237 || 554 || Cabinetry
|-
| 360 || 355 || The Shire
|-
| 464 || 562 || Brandon
|-
| 567 || 567 || Hamwich
|-
| 356 || 577 || West Norsussex
|-
| 420 || 578 || Redsox
|-
| 502 || 590 || Keebler
|-
| 372 || 597 || Lionsgate
|-
| 229 || 597 || Bloughshire
|-
| 573 || 609 || Kingsbottom
|-
| 182 || 613 || Aberforth
|-
| 328 || 615 || South Norwessex
|-
| 244 || 617 || Dryford
|-
| 495 || 630 || Frampton
|-
| 477 || 634 || Cambridge
|-
| 251 || 635 || Kingsfriend
|-
| 539 || 652 || Cair Paravel
|-
| 235 || 655 || Camelot
|-
| 408 || 655 || Nothingham
|-
| 429 || 673 || Cumberbatch
|-
| 121 || 673 || The CW
|-
| 303 || 674 || Dampshire
|-
| 210 || 676 || Whaling
|-
| 511 || 690 || Paulblart
|-
| 397 || 693 || Oxford
|-
| 169 || 695 || Moohren
|-
| 255 || 706 || Cardigan
|-
| 462 || 710 || GMT
|-
| 445 || 711 || London
|-
| 308 || 716 || Corbyn
|-
| 507 || 729 || Tems-Upon-Thames
|-
| 161 || 737 || BBC Channel 4
|-
| 267 || 737 || Minas Tirith
|-
| 560 || 746 || Hogsmeade
|-
| 454 || 748 || Tubemap
|-
| 296 || 756 || Cambnewton
|-
| 398 || 765 || Efrafa
|-
| 186 || 767 || Oughghough
|-
| 536 || 767 || Chansey
|-
| 351 || 777 || Sundial
|-
| 370 || 782 || Dobby
|-
| 162 || 784 || Lower Bottom
|-
| 496 || 784 || Menthol
|-
| 362 || 796 || Southframpton
|-
| 56 || 800 || West Sea
|-
| 154 || 804 || Blandford
|-
| 216 || 824 || Tarp
|-
| 123 || 846 || Longbit
|}

==Transcript==
Helcaraxë, Blick, Everdeen, Norther Sea, Highlands, Lock Lomond, Fjordham, A British Map Labeled by an American, Glassdoor, Eavestroughs, Seasedge, Chough, Meowth, (A picture of an upsidedown protractor), Blighton, Eyemouth, Glutenfree, North Sea, Earhand, Hairskull, Belfast DeVoe, Lakebottom, Braintree, Skinflower, Bjork, Weedle, Eeugh, Crewneck, Paisley, Basil, Aidenn, Waterdown, Hillfolk, Dubstep, Borough-Upon-Mappe, Fhqwhgads, Landmouth, Cadbury, Cabinetry, The Shire, Brandon, Hamwich, West Norsussex, Redsox, Keebler, Lionsgate, Bloughshire, Kingsbottom, Aberforth, South Norwessex, Dryford, Frampton, Cambridge, Kingsfriend, Cair Paravel, Camelot, Nothingham, Cumberbatch, The CW, Dampshire, Whaling, Paulblart, Oxford, Moohren, Cardigan, GMT, London, Corbyn, Tems-Upon-Thames, BBC Channel 4, Minas Tirith, Hogsmeade, Tubemap, Cambnewton, Efrafa, Oughghough, Chansey, Sundial, Dobby, Lower Bottom, Menthol, Southframpton, West Sea, Blandford, Tarp, Longbit

{{comic discussion}}

1755: Old Days

2016-11-04T20:42:20Z

Wargames: /* Table of statements */

{{comic
| number = 1755
| date = November 4, 2016
| title = Old Days
| image = old_days.png
| titletext = Lot of drama in those days, including constant efforts to force the "Reflections on Trusting Trust" guy into retirement so we could stop being so paranoid about compilers.
}}

==Explanation==
{{incomplete|More explanation required on computer programming. Fill out the explanation column in the [[#Table of statements|table]] that lists all the statements.}}
This comic is showing a conversation between (young) [[Cueball]] and (old) [[Hairbun]] about computer programming in the past, specifically the {{w|compilers}}. Cueball, having a faint idea of just how difficult and byzantine programming was "in the old days", asks Hairbun to enlighten him on the specifics. Hairbun promptly seizes the opportunity to screw with his head.

While her initial explanation that code needed to be compiled for multiple architectures is correct, Hairbun's claims rapidly grow ridiculous to the point where the improvement from {{w|C (programming language)|C}} to {{w|C++}} was that C++ finally supported {{w|floppy disks}} but just punched holes in them rather than using {{w|punch cards}} "like C used". (A notch in the side of 5.25" floppy disks indicates when the disk could be written. Though many floppy disks were intended to have only a single side with data, many people used a hole punch to notch the opposite side of the disk, allowing a drive to write data to the other side of the disk in a single sided drive.)

Hairbun tells Cueball a tall tale about how hard it was back in the '''old days''', making it sound like some of the programming languages used today (C, C++) were written on punch cards and that you had to ship your code in the mail to a computer company ({{w|IBM}} in this case) to compile your code, which would take from four to six weeks. If there was a simple error, you would have to ship it again for another compilation.

Nothing of what she tells Cueball makes any sense, but it is clear from Cueball's final ''Wow'' that he falls for it, ready to believe anything the old Hairbun tells him about how horrible it was to program in the olden days. It is true that it was tough and slow to program on punch cards, which were actually used for an extended period of time, but there is nothing in the rest of Hairbun's story that accurate, except that it was a big deal when the floppy disk was invented.

In the title text, Hairbun continues her musings on the old compiler days, stating that there was ''a lot of drama in those days''. Specifically the references ''[http://www.win.tue.nl/~aeb/linux/hh/thompson/trust.html Reflections on Trusting Trust]'' a famous 1984 paper by {{w|UNIX}} co-creator {{w|Ken Thompson}} in which he described a way to hide a virtually undetectable backdoor in the UNIX login code via a second backdoor in the C compiler. Using the technique in his paper, it would be impossible to discover the hacked login by examining the official source code for either the login or the compiler itself. Ken Thompson may have actually included this backdoor in early versions of UNIX, undiscovered. Ken Thompson's paper demonstrated that it was functionally impossible to prove that any piece of software was fully trustworthy.

Hairbun claims that one of the dramas she refers to was that people tried to force Ken Thompson to retire, so everyone could stop being so paranoid about compilers. In reality, any coder who created the first version of a compiler (or a similar critical component) could inject a similar backdoor into software, so it would be false safety. Even if no one else had thought of this, then Thompson's paper was there for any future hacker to see. Though the problem was (claimed to be) solved in {{w|David A. Wheeler}} Ph.D dissertation "[http://www.dwheeler.com/trusting-trust/ Fully Countering Trusting Trust through Diverse Double-Compiling (DDC)]".

==Table of statements==
{|class="wikitable"
!Statements
!Concepts used
!Explanation
|-
|Compile things for different processors
|Compilers convert code from a human-readable programming language into a binary code that can be directly executed by computer processors.
|Many popular modern programming languages are either interpreted - meaning that they run directly from source code - or compile to an intermediate bytecode, like Java or common Python implementations. Programs written in such languages are portable across processor architectures - x86 to ARM, for example. Lower-level languages must take into account the features available on a given processor architecture and operating system. Before that, programs needed to compile directly into the native machine language for each processor they were intended to run on.
Native machine language is dependent on processor architecture. Therefore different processors designed around different architectures will not run the same compiled code (unless the architectures are compatible; AMD64 processors will run i386 code natively, for example.) If the same code needs to be run on multiple architectures, it must be compiled separately for each supported architecture.
|-
|To compile your code, you had to mail it to IBM. It took 4-6 weeks.
|Similar to sending Kodachrome slide film to Kodak to be developed.
|While IBM has released multiple compilers, they sent the compiler to you, you did not send the code to them. There is some kind of truth in the statement, though: When programming on mainframes, programmers submitted their source code in the evening for compilation over night. When there was an error in the code, they did not get a compiled version of it back, and had to resubmit their code. Sometimes there were time slots available for compilation, and in universities, students will have to wait for their next time slot for another try.
|-
|Before garbage collection, data would pile up until the computer got full and you had to throw it away.
|A {{w|Garbage collection (computer science)|garbage collector}} is a piece of the software that cleans the {{w|RAM}} of data that is no longer being used in the execution of a program.
|Hairbun's comment is grounded in reality. Garbage collection is a form of memory management that generally destroys objects or frees up memory once a program no longer needs it. In languages without automatic memory management, like C, the program itself must keep track of what memory has been allocated, and free it once it is no longer needed. If the program does not, it can end up trying to use more memory than the computer has, and may crash. This was, however, a ''temporary'' condition. In the worst case, a simple reboot will clear the computer's memory.
|-
|Early compilers could handle code fine, but comments had to be written in assembly.
|A {{w|Comment (computer programming)|comment}} in programming is a text written in natural language that is meant to explain some feature of the source code; it is tagged such that the compiler will discard it to save space. {{w|Assembly}} is a low-level programming language.
|Comments, in code, are portions of one or more lines that are ignored by the compiler. They are commonly used to explain or comment on the code itself. But sometimes the comments are written in a certain way to compile documentation automatically from it. Also, when examining the output of compilers it's a common practice to use assembly code annotated with comments containing the source code of the program from which the assembly code was generated.

Hairbun's comment is thus very strange, implying the compilers of the day could only distinguish between comments and code if assembly was used to insert the separating tags.
|-
|C could only be written on punch cards. You had to pick a compact font, or you'd only fit a few characters per card.
|{{w|C (programming language)|C}} is a programming language. A {{w|punch card}} is a primitive form of storing data; it stored data in {{w|binary language}} with holes in a paper or cardboard card where a hole meant a 1 and the absence of a hole meant a 0.
|While punch cards were used through the late 1970s and early 1980s to enter programs and data in COBOL, FORTRAN and other early languages, the use of punch cards and punch card machines had been replaced by a {{w|text editor}} long before C (or C++) was developed as a language. This site demonstrates a card punch and cards http://www.masswerk.at/keypunch/

Hairbun claims that code was not written using keyboards, but by punching out letter and character shapes in the punch cards, and the computer would load read keystrokes that way. Simply put, this was never true. Punch cards store characters in binary; there is no font involved and they store up to fixed limit of characters per card (80 characters in the most common format.)
|-
|C++ was big because it supported floppy disks. It still punched holes in them, but it was a start.
|{{w|C++ (programming language)|C++}} is a programming language. A {{w|floppy disk}} is a form of storing data magnetically. It's more advanced than punch cards, but it's still old.
|Hairbun says that the improvement from C to C++ was that C++ finally "supported floppy disks", but then it turns out that in C++ the floppy disks were just used instead of punch cards. So the programing was to make holes in floppy disks rather than punch cards. This would of course not be an improvement as floppy disks store information magnetically, as opposed to physically, as punch cards do. This is likely a play on the concept of punching holes in 5.25" floppy disks to double their storage (Source: https://en.wikipedia.org/w/index.php?title=Double-sided_disk&oldid=713168494).
|}

==Transcript==
:[Cueball and Hairbun are standing together and Cueball is talking to her.]
:Cueball: What were things like in the old days?
:Cueball: I hear that you had to ... compile things for different processors?
:Hairbun: Yeah

:[Same setting in a slimmer panel, now Hairbun is replying.]
:Hairbun: To compile your code, you had to mail it to IBM.
:Hairbun: It took 4-6 weeks.

:[Close-up of Hairbun from the waist up.]
:Hairbun: Before garbage collection, data would pile up until the computer got full and you had to throw it away.

:[Same setting as in the first panel with Hairbun gesturing toward Cueball raising one hand palm up.]
:Hairbun: Early compilers could handle code fine, but comments had to be written in assembly.

:[In a frame-less panel Hairbun is seen from the front, with both arms out to the side with both hands held palm up.]
:Hairbun: '''C''' could only be written on punch cards.You had to pick a compact font, or you'd only fit a few characters per card.

:[Exactly the same setting as the first panel, but with Hairbun doing the talking.]
:Hairbun: '''C++''' was big because it supported floppy disks.
:Hairbun: It still punched holes in them, but it was a start.
:Cueball: Wow.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Hairbun]]
[[Category:Programming]]

1755: Old Days

2016-11-04T14:56:56Z

Wargames: /* Table of statements */

{{comic
| number = 1755
| date = November 4, 2016
| title = Old Days
| image = old_days.png
| titletext = Lot of drama in those days, including constant efforts to force the "Reflections on Trusting Trust" guy into retirement so we could stop being so paranoid about compilers.
}}

==Explanation==
{{incomplete|More explanation required on computer programming. Fill out the explanation column in the [[#Table of statements|table]] that lists all the statements.}}
This comic is showing a conversation between (young) [[Cueball]] and (old) [[Hairbun]] about computer programming in the past, specifically the {{w|compilers}}. Cueball, having a faint idea of just how difficult and byzantine programming was "in the old days", asks Hairbun to enlighten him on the specifics. Hairbun promptly seizes the opportunity to screw with his head.

While her initial explanation that code needed to be compiled for multiple architectures is correct, Hairbun's claims rapidly grow ridiculous to the point where the improvement from {{w|C (programming language)|C}} to {{w|C++}} was that C++ finally supported {{w|floppy disks}} but just punched holes in them rather than using {{w|punch cards}} "like C used". (A notch in the side of 5.25" floppy disks indicates when the disk could be written. Though many floppy disks were intended to have only a single side with data, many people used a hole punch to notch the opposite side of the disk, allowing a drive to write data to the other side of the disk in a single sided drive.)

Hairbun tells Cueball a tall tale about how hard it was back in the '''old days''', making it sound like some of the programming languages used today (C, C++) were written on punch cards and that you had to ship your code in the mail to a computer company ({{w|IBM}} in this case) to compile your code, which would take from four to six weeks. If there was a simple error, you would have to ship it again for another compilation.

Nothing of what she tells Cueball makes any sense, but it is clear from Cueball's final ''Wow'' that he falls for it, ready to believe anything the old Hairbun tells him about how horrible it was to program in the olden days. It is true that it was tough and slow to program on punch cards, which were actually used for an extended period of time, but there is nothing in the rest of Hairbun's story that accurate, except that it was a big deal when the floppy disk was invented.

In the title text, Hairbun continues her musings on the old compiler days, stating that there was ''a lot of drama in those days''. Specifically the references ''[http://www.win.tue.nl/~aeb/linux/hh/thompson/trust.html Reflections on Trusting Trust]'' a famous 1984 paper by {{w|UNIX}} co-creator {{w|Ken Thompson}} in which he described a way to hide a virtually undetectable backdoor in the UNIX login code via a second backdoor in the C compiler. Using the technique in his paper, it would be impossible to discover the hacked login by examining the official source code for either the login or the compiler itself. Ken Thompson may have actually included this backdoor in early versions of UNIX, undiscovered. Ken Thompson's paper demonstrated that it was functionally impossible to prove that any piece of software was fully trustworthy.

Hairbun claims that one of the dramas she refers to was that people tried to force Ken Thompson to retire, so everyone could stop being so paranoid about compilers. In reality, any coder who created the first version of a compiler (or a similar critical component) could inject a similar backdoor into software, so it would be false safety. Even if no one else would have thought of this, then Thompson's paper was there for any future hacker to see. Though the problem was (claimed to be) solved in {{w|David A. Wheeler}} Ph.D dissertation "[http://www.dwheeler.com/trusting-trust/ Fully Countering Trusting Trust through Diverse Double-Compiling (DDC)]".

==Table of statements==
{|class="wikitable"
!Statements
!Concepts used
!Explanation
|-
|Compile things for different processors
|Compile?
|Many popular modern programming languages are either interpreted - meaning that they run directly from source code - or compile to an intermediate bytecode, like Java or common Python implementations. Programs written in such languages are portable across processor architectures - x86 to ARM, for example. Lower-level languages must take into account the features available on a given processor architecture and operating system. Before that, even, programs needed to compile directly into the native machine language for each processor they were intended to run on.
|-
|To compile your code, you had to mail it to IBM. It took 4-6 weeks.
|Similar to sending Kodachrome slide film to Kodak to be developed.
|While IBM has released multiple compilers, they sent the compiler to you, you did not send the code to them. There is some kind of truth in the statement, though: When programming on mainframes, programmers submitted their source code in the evening for compilation over night. When there was an error in the code, they did not get a compiled version of it back, and had to resubmit their code. Sometimes there were time slots available for compilation, and in universities, students will have to wait for their next time slot for another try.
|-
|Before garbage collection, data would pile up until the computer got full and you had to throw it away.
|A {{w|Garbage collection (computer science)|Garbage Collector}} is a piece of the software that cleans the {{w|RAM}} memory of data that is no longer being used in the execution of a program.
|Garbage collection is a form of memory management that generally destroys objects or frees up memory once a program no longer needs it. In languages without automatic memory management, like C, the program must keep track of what memory has been allocated, and free it once it is no longer needed. If the program does not, it can end up trying to use more memory than the computer has, and may crash. This was, however, a temporary condition. In the worst case, a simple reboot will clear the computer's memory.
|-
|Early compilers could handle code fine, but comments had to be written in assembly.
|A {{w|Comment (computer programming)|comment}} in programming is a text written in natural language that is meant to explain some feature on the source code. {{w|Assembly}} is a low-level programming language.
|Comments, in code, are portions of one or more lines that are ignored by the compiler. They are commonly used to explain or comment on the code itself. But sometimes the comments are written in a certain way to automatically compile manuals from it.
|-
|C could only be written on punch cards.You had to pick a compact font, or you'd only fit a few characters per card.
|{{w|C (programming language)|C}} is a programming language. A {{w|punch card}} is a primitive form of storing data; it stored data in {{w|binary language}} with holes in a paper or cardboard card where a hole meant a 1 and the absence of a hole meant a 0.
|While punch cards were used through the late 1970s and early 1980s to enter programs and data in COBOL, FORTRAN and other early languages, the use of punch cards and punch card machines had been replaced by a {{w|Text Editor}} long before C (or C++) was developed as a language.

Also, as punch cards encode characters as punched holes, there is no font involved and they store up to fixed limit of characters per card (80 characters in the most common format.) There is a really cool example of this at The Virtual Keypunch Machine at http://www.masswerk.at/keypunch/

|-
|C++ was big because it supported floppy disks. It still punched holes in them, but it was a start
|{{w|C++ (programming language)|C++}} is a programming language. A {{w|Floppy disk}} is a (more advanced than punch cards but still old) form of storing data magnetically.
|Hairbun says that the improvement from C to C++ was the C++ finally supported floppy disks, but then it turns out that in C++ the floppy disks were just used instead of punch cards. So the programing was to make holes in floppy disks rather than punch cards. This would of course not be an improvement as floppy disk are not as easy (actually very hard) to make holes in, compared to punch card, which are made for this purpose and then the whole concept of using floppy disk to store data magnetically is ignored (you could not re-use the floppy again). In any case, a hole punched in a floppy disk would render it useless.
|}

==Transcript==
:[Cueball and Hairbun are standing together and Cueball is talking to her.]
:Cueball: What were things like in the old days?
:Cueball: I hear that you had to ... compile things for different processors?
:Hairbun: Yeah

:[Same setting in a slimmer panel, now Hairbun is replying.]
:Hairbun: To compile your code, you had to mail it to IBM.
:Hairbun: It took 4-6 weeks.

:[Close-up of Hairbun from the waist up.]
:Hairbun: Before garbage collection, data would pile up until the computer got full and you had to throw it away.

:[Same setting as in the first panel with Hairbun gesturing toward Cueball raising one hand palm up.]
:Hairbun: Early compilers could handle code fine, but comments had to be written in assembly.

:[In a frame-less panel Hairbun is seen from the front, with both arms out to the side with both hands held palm up.]
:Hairbun: '''C''' could only be written on punch cards.You had to pick a compact font, or you'd only fit a few characters per card.

:[Exactly the same setting as the first panel, but with Hairbun doing the talking.]
:Hairbun: '''C++''' was big because it supported floppy disks.
:Hairbun: It still punched holes in them, but it was a start.
:Cueball: Wow.

{{comic discussion}}

[[Category:Comics featuring Cueball]]
[[Category:Comics featuring Hairbun]]
[[Category:Programming]]