I like the broader question this inspires: Why are the technologies prevalent in the 60's still prominent today? The correct, standard answer is that they're good enough. Good enough often beats out better solutions. But that's only half of the story. Embrace that theory too much, and we'll find ourselves in a world of good enough solutions.
I don't know about you, but I don't want the world to be "good enough". I want it to be better. We could accept all of what we have today, and take it for granted, and we'd live with it forever. But that would suck.
Even the most entrenched technologies can be displaced, or even replaced, with enough ingenuity, effort, and a superior technology. Most changes are happening slowly, as they must when we have billions of "installs". Most won't replace their predecessor completely, but erode it slowly:
IPv4 to IPv6.
Windows to OS X.
SOAP to REST.
XML to JSON.
HTTP to SPDY.
IE to Chrome.
Flash to Canvas.
Those changes didn't happen automatically; people pushed to get those new ideas out there. Truly better software will make it, but it won't happen if you accept that the old guard is here forever.
Forever is a long time.
One more thing: Many things that are really old — Unix, for instance — aren't the same as they were before. They've evolved, changed, and grown as developers evolve the software. Emacs today is tremendously different from its first release. Software evolves, and often dies when it doesn't.
TeX is an odd case, because it has been replaced in much of the world, with the almost-sole exception of mathematical and computer science academic writing. The vast majority of people doing typesetting of anything else (e.g. books, even at academic presses like MIT Press) will use a newer typesetting engine (one of the high-priced proprietary ones).
My guess is it just takes far too much implementation effort to replicate (or even significantly modify) something like TeX relative to the fairly small userbase of academic-paper-writers. The low-level typesetting-related parts in particular are pretty hairy and hard to get right, so experimentation tends to happen more in higher-level macro packages.
Afaik, Adobe InDesign and Quark dominate the market, with InDesign being the de-facto standard. They're not as high-priced or numerous as they used to be, though; there were a bunch of sold-to-professionals-only packages in the 80s, but there seems to have been a convergence between desktop publishing and professional print prepress, so everyone just uses InDesign or Quark now.
You are only considering old technology versus new. There are old things that are much better than their newer counterparts. Take S-expressions for instance, or Lisp, or Tex.
These things worked amazingly well, yet managed to be replaced by lesser technologies.
Programming languages show clearly one of the reasons why this happens : the benefits might not be immediately obvious. You don't know what abstractions you are missing until you have taken the time to learn them and express your ideas with them.
In the case of Lisp, and Tex, there is also a huge problem of marketing.
To take your examples :
IPv6 is basically a necessity.
Windows to OS X is not really happenning seriously
SOAP and XML suck so bad that the benefits of REST and JSON are mostly oubvious
Chrome was well marketed, and purports to replace the obviously bad IE. It brings with it SPDY and Canvas.
"""There are old things that are much better than their newer counterparts. Take S-expressions for instance, or Lisp, or Tex."""
1) There are today tons of BETTER Lisp-like languages than 60's Lisp.
2) What are the "newer counterparts" that S-expressions are better from? Here's a few propositions for something better than old style S-expressions: http://www.dwheeler.com/readable/
And from a pragmatic standpoint, one can even argue that (more modern) C is even better than Lisp/S-expressions, because it has enabled orders of magnitude more used and useful software, include the whole of Unix/Windows/OS X/Linux, etc.
3) Putting TeX on this list makes it a vicious circle. You cannot explain why TeX has not been surpassed by something better by invoking TeX being better that anything newer.
This is not a thread for lisp/sexp discussions, but the better sexp miss the important point that:
define some(x y z)
code goes here
should not be any different for the compiler, especially the way humans understand what the compiler does, than a simple list/array:
(1 2 3 4)
This way, you can mess with code the same way you do it with normal data structures, replace parts, add things etc.
The way they are writing it, "define" looks like a keyword, just like "if" and "for" is, in most of the languages, instead of a function, just like everything else in lisp is.
"We could accept all of what we have today, and take it for granted, and we'd live with it forever. But that would suck." The inverse of that is having everything change so quickly that we can't ever accomplish anything. It's all about striking that balance between improving tools and making the product or service.
Given how long Fortran has lasted in the scientific community, something is going to have to be remarkably better than TeX for people to switch. Old ways die slowly, especially in the sciences. As Kuhn's Structure of Scientific Revolutions observed, old ideas are usually only replaced when the old people die.
Or IE to Chrome specifically. Speaking personally I find Chrome very feature-poor and much prefer Firefox, and nothing that's changed in recent releases from either looks likely to change that opinion.
It confuses the hell out of me that I'm defending Windows here - I'm an OSS enthusiast and run Linux whenever I can.
Thing is: Operating systems are at this point just a more complex choice of preference and taste. Pick anything recent (I'm not going to stand for Win 95/98/ME/XP), use common sense and best practices for the platform and you're golden.
No, OS X is not by default a better system. It might attract you as a BSD with a UI that you consider damn fine. Other people are free to disagree and like their choice of platform better, be it Windows, Linux, *BSD or whatnot.
I repeat: There's _zero_ ground for calling OS X generally superior (nor inferior!) in a war of operating systems, neither technically nor in any other way.
It would be super tough to replace TeX for its intended users and uses.
There was a GRIM problem -- getting math typed for high quality work in math, science, engineering, and technology. TeX was a terrific solution. The problem has not much changed, and TeX remains a terrific solution.
Or the problem was to put black marks on white paper with math and English with high quality. Now we put black marks on a white background in a PDF file -- fine. How to do that was the problem, and TeX is a terrific solution. Or, the intended TeX users are for the intended uses concerned mostly with the math, just the math. For the math, we need the TeX math fonts and the AMS fonts and how TeX formats the math in 2D, but we don't need color, 3D, GUIs, popups, pull downs, rollovers, animation, hot links, text boxes, radio buttons, drag and drop, icons, etc.
Good TeX users have lots of macros for TeX, editor macros for TeX, papers in TeX, knowledge of TeX, documentation of TeX, skills with TeX, and journals that will accept papers in TeX and don't want to lose these or replace them.
For 'what you see is what you get' (WYSIWYG), 'what you see is all you've got', and for the intended users and uses, WYSIWYG is very much a step backwards (I would yell and scream bloody murder) and NOT wanted.
Similarly I care from not very much down to not at all for support of all of Unicode, color, graphics, animation, direct output of PDF, output of HTML/CSS, 3D, CAD features, etc.
For a lot more in functionality, I don't want to struggle with a LOT more in documentation, quality likely much lower than TeX directly from the hands of Knuth, years of bug fixes and version changes, time to acquire skills, time to write new macros, effort to struggle with journals that still want TeX instead of something new, etc.
TeX is one of my most important tools. To have me give up TeX will require twisting it out of my cold, dead fingers.
Net, there was grim problem, and it has not much changed. TeX was and remains a terrific solution. Done. That TeX won't slice bread is just irrelevant.
Unix is still the same (in some ways) as before because Unix had a remarkably simple mental model, and the ways we try to replace them don't. Unix didn't last forever because it had features, good god! No, it's because it was so robust and flexible as to serve even a modern system. TeX, and Unix, and all these things, were hackable. (If you don't agree about TeX, read the TeXbook and some traditional TeX, not this LaTeX crap that's grown around it.) That doesn't mean it these systems are irreplaceable. (Hell, I'm working on a project to replace the Unix shell...) It just means you need to put more effort into devising a very good mental model. Something that actually captures all of the variation you want. So, don't replace TeX because you don't like TeX. Replace TeX because you have something better, something obviously better, something that you could explain to a five-year-old.
This would seem a problem that could be solved by a cloudish sort of solution, though -- have an iPad app which hands actual typesetting of a document off to a server somewhere, sending TeX sources, and receiving a PDF in return.
A simple starter implementation might require your TeX to be a single file, and could just run TeX in a mostly-readonly chroot jail (bearing in mind that TeX can shell out, read/write arbitrary files readable by the executing user, and so on), and serve up a PDF, all wrapped in a web service of some sort.
This wouldn't be terribly fast, but given TeX's performance, the actual typesetting is likely to be the bulk of the time spent, even considering the round trip.
"It’s comforting to think that all the TeX documents I’ve written over the years will still be readable a century hence. But Mind Two reminds me that in practice I have trouble maintaining TeX documents even for a few months, much less decades or centuries."
but here his concern is NOT about "TeX documents" but about LaTeX documents.
They are not the same.
(2) From dextorious.
About Issue 1, dextorious wrote:
"And that is just a pedantic excuse, that no one cares about. People don't use TeX itself (and, to prevent another pedantic detail, I mean the vast majority of people), people use LaTeX+TeX."
No. The claim:
"People don't use TeX itself".
is false: I use TeX itself, a lot; I'm a Ph.D. applied mathematician and, thus, use TeX for math. In fact, for math, I know of no reasonable substitute except for LaTeX which I don't like as well as just TeX.
Then, since I have TeX and know how to use it, it is also my main high quality word whacking software; I use it for letters, technical papers, foils, and even business cards. I essentially never use LaTeX. And I have a version of Word and nearly never use it either. E.g., even for just simple letters, I much prefer TeX to Word.
That I actually use TeX itself is not "another pedantic detail" because one of the main reasons I won't use LaTeX is JUST the objection of the author that LaTeX is not stable: I want the stability of TeX. E.g., I have over 100 macros in TeX. Nearly all of these were written in the 1990s. When I changed to Windows XP, I copied over all my TeX macros, and all of them have continued to work just as before just as Knuth guaranteed. GOOD.
(3) TeX Doesn't Slice Bread.
There is no one tool that can do everything, and it would be foolish to hope for such a tool.
Knuth was extraordinarily careful about saying just what TeX was, providing some exemplary documentation, and then essentially freezing everything for all time.
The author criticizes TeX for not being what the author wants. This is not fair or even reasonable.
It would be fair to criticize TeX for failing to do what Knuth promised. But it's not fair to criticize TeX for not being something it was not intended or promised to be.
It's not fair or even reasonable to criticize a Stradivarius violin because it is not a Steinway piano, French food because it is not Chinese food, a car because it is not a truck, etc.
As software goes, LaTeX is relatively stable, but the author criticizes LaTeX on stability. So, (A), the author wants stability, more than LaTeX has. But, (B) the author wants more in user interface and likely languages, alphabets, fonts, color, cross references, maybe rotations and other transformations, likely spell checking and hyphenation in many languages, graphics, maybe with sound and video, etc. And we have to assume the author also wants the ability to do well setting math. Then in practice (A) and (B) conflict: That is, trying to provide the much greater functionality of (B) will mean years and years of revisions that conflict with the stability of (A).
Well, I have good news for the author: It's been a secret and ABSOLUTELY not to be distributed beyond this thread. So far known by no more than a very few people, the UN has funded, starting some years ago, a unique software development effort in a monastery in Tibet to develop UniTeX, word whacking software that will handle all of the Unicode alphabets and their languages with spell checking and hyphenation along with 48 bit color, 3D, resolution from 600 pixels per line to tens of thousands, execution on super computers down to cloud servers, desktops, laptops, palmtops, tablets, mobile phones, wrist watches, and magic decoder rings, many thousands of fonts, Haskell, for at least 1000 cores, as the macro language, all of the functionality of Distiller, PhotoShop, Final Cut Pro, and AutoCad, output on paper, PDF, AVI, Flash, SilverLight, and MP3, and much more. Version 1.0 will be released when all the functionality has been implemented and is at least as stable as TeX. Then version 1.0 will be the last version. The project will be open source, but the name UniTeX will be reserved for the one, only, genuine, guaranteed authentic, dyed in the wool, UN UniTeX. The release date for version 1.0 is currently set at year 2100.
In the meanwhile, TeX is what it was intended to be. I believe that TeX, just as it is, is terrific for all my higher quality word whacking.
The main target audience for TeX is writers of the most serious work in subjects with a lot of mathematical notation in math, science, engineering, and technology. For such writing, TeX remains quite good. E.g., the emphasis on English, black and white for the fonts, the prominence of the TeX Computer Modern fonts and the AMS fonts, the stability, etc. are all reasonably appropriate. In particular, it will not be easy to get the relevant academic journals to give up TeX in order to get a lot more in color, fonts, alphabets, etc.
Information technology entrepreneurship is a very active field, especially in Silicon Valley. So, someone who wants more than TeX could do a startup. My view is that getting a good combination of product stability, product functionality, product development cost and time, user adoption, and revenue with the good features of TeX and much more, that is, getting what the author wants, would not be promising. Or, Knuth worked hard on TeX for what, over 10 years; doing a lot more would take much more, would take too darned much.
Finally, there is another point about TeX: Before TeX, getting math typed was just GRIM. Typically the typing was much more difficult than the math. TeX made it quite reasonable to get math typed. GREAT.
TeX is so good that now the challenge is the math and not the typing.
For the main intended users and uses of TeX, e.g., Knuth and his writing, TeX is fine, and changing to something else just is not worth the effort.
In particular, Unicode, color, a graphical user interface (GUI), etc. are from not worth the bother down to very much not welcome.
Net, there was a big problem. TeX provided an excellent solution to the problem. The problem has not much changed and remains solved. Done.
The article has several issues of 'drama' regarding TeX. All of these issues are just contrived to have drama for the sake of drama; none of these issues is a serious comment about TeX.
I discuss six such issues:
Issue 1.
The article has:
"It’s comforting to think that all the TeX documents I’ve written over the years will still be readable a century hence. But Mind Two reminds me that in practice I have trouble maintaining TeX documents even for a few months, much less decades or centuries. What about those presentations done with the foils class that stopped working after an upgrade and that I’ve never bothered to fix? Or the articles using the pstricks package that won’t compile under pdflatex? TeX itself may be a fixed point in the software universe, but everything else spins dizzily around it."
So, here the author seems to have a 'dramatic issue' to grab the reader by the heart and/or the gut. Yes, 'writers' tend to do that.
Of course, strictly this "issue" is 100% total nonsense: The problems he listed are all about LaTeX which strictly just is NOT the same as TeX, that is, as in:
Donald E. Knuth, 'The TeX book', ISBN 0-201-13448-9, Addison-Wesley, Reading, Massachusetts, 1990.
with the macros there called Plain.
Or LaTeX is as in, say,
Helmut Kopka and Patrick W. Daly, 'Guide to LaTeX, Fourth Edition', ISBN 0-321-17385-6, Addison-Wesley, Boston, 2004.
and
Frank Mittlebach and Michel Goosens with Johannes Braams, David Carlisle, and Chris Rowley, with contributions by Christine Detig and Joachim Schrod, 'The LaTeX Companion, Second Edition', ISBN 0-201-36299-6, Pearson Education, Boston, 2004.
and in these two books we do not see Knuth's name.
So, can't blane the problems of LaTeX on Knuth or TeX.
So, his:
"It’s comforting to think that all the TeX documents I’ve written over the years will still be readable a century hence."
Good. So, with TeX, just TeX, that is, just Knuth's TeX itself and not LaTeX, FakeTeX, JunkTeX, or NotTeX, the author of the article of this thread can remain comforted.
Issue 2.
Yes, the 'writer' seems to like drama more than rationality since he also has:
"The skeptical Mind Two has another argument as well: Under Knuth’s edict it’s not just the TeX markup language that can’t change; it’s also the architecture of the system. Knuth created his flawless soufflés and dæmon diarrhœa at an ASCII terminal wired to a PDP-10, and the only way he could see the product of his labors was to walk down the hall and retrieve hard copy from the AlphaType machine."
But the "architecture of the system" has nothing to do with "walk down the hall and retrieve hard copy from the AlphaType machine". Instead, part of the "architecture" is the guarantee:
"His intent in freezing TeX is to ensure that the same input should always yield the same output."
and that guarantee continues to hold without a "hall" or "AlphaType" machine. How? Because the guarantee was about the output of TeX which was just a file of type DVI (which abbreviates 'device-independent file'). The TeX I continue to use as my most important word whacking software continues to put out a DVI file and appears still to meet the guarantee.
Issue 3.
The author goes on with
"But the core programs still run in batch mode, as they did in the Dark Ages. To make even the smallest change in a document, you still need to throw away all the existing output and run a whole file (or set of files) through the compiler tool chain."
Of course. He should expect something else? I have two responses:
First, what's wrong with "batch mode"? What else is to be done? As any Web site designer knows, due heavily to the 'sessionless' model of the Web, the server code for a Web page in HTML and CSS (but not necessarily Ajax) runs essentially in 'batch mode'.
Second, even a little reading of Knuth's book above shows that it would not be easy to be given a change in the input and then to get significant computational savings by determining what fraction of the output can be saved and not calculated again. So, we calculate all the output again.
Issue 4.
Next, the author has:
"Sometimes you have to do it twice."
Not due just to using TeX! However, TeX does permit writing to a file and reading from a file. So if want to use such file writing/reading to generate, say, cross references, then will need to run TeX more than once. But the effects of such writing/reading are due to the user and not to TeX. In particular, we can notice that in Knuth's book, there are no cross references that would require running TeX more than once.
Or, as we can see from reading Knuth's book, it is not easy to know exactly where will be the break betwoen one page and the next. Then it will not be easy to do cross references accurate to the page number. So, in Knuth's book, he didn't.
Sure, in my usage of TeX, I have some macros for cross references to the page number, but my macros can occasionally make a mistake and, thus, are not up to the quality of TeX.
I am sure Knuth saw this issue but wanted the high quality page breaking more than some automated cross references.
Issue 5.
The article has:
"By then we’ll just throw Moore’s Law at it: Automatically rerun TeX n times for every keystroke in the editor."
Here the author is implicitly assuming that, of course, a word whacking system SHOULD be based on an 'interactive interface' with 'what you see is what you get', one keystroke at a time. That's a very specific assumption that would be quite questionable at any time and otherwise would tend to 'date' TeX.
For me, I would reject that assumption. That is, absolutely, positively I do NOT want TeX to have an 'interactive interface', to be 'what you see is what you get', or to do word whacking for each of my keystrokes. I do NOT want such things.
In particular, I want to be able to run TeX in a 'batch script' with, "Look, Ma, no hands.". That is, I want TeX to remain something that can do its work without my being there, that is, part of the future where computers do work without a human giving full attention at each keystroke.
In particular, a good response to 'what you see is what you get' (WYSIWYG) is that with such an 'interactive interface' 'what you see is all you've got' and that's not very much.
What can there be that is not seen? Sure, can have a 'conception' for the document and parts of it and have some macros that contribute to this conception. Or, the macros automate parts of the conception. E.g., want a macro for the page headers. Then all the page headers look as in the conception for the page headers. Strictly with WYSIWYG, would have to type in the header for each page individually and, then, struggle to get them all as in the conception. Similarly for how to number sections, subsections, figures, tables, and equations and much, much more.
Issue 6.
I would agree with the author that TeX does not bake bread, drive a car, vacuum the carpet, recognize human speech, do the calculations for computer generated scenes in movies, etc.
Instead, TeX was mostly just for what Knuth said it was for, "beautiful books", especially ones with quite a lot of mathematics. Moreover, implicit was that tbe books would be essentially in English. E.g., the hyphenation was for English, and no fonts were provided for text in Cryllic, Fraktur, Arabic, etc. In particular, the characters were to be from 7 bit ASCII and not 8 bit whatever or Unicode.
Consider his "books": TeX was looking backwards in time, that is, was intended to be a computer version of traditional, beautiful typesetting for BOOKS, just such BOOKS, and not something different, better, for the future, etc.
Knuth didn't say 'beautiful PDF files', 'beautiful Web pages', or 'striking foils with voice over, background music, and multi-touch gesture recognition', etc.
So, there is a lot that TeX is not. Right.
There's no 'drama' in saying that TeX won't sweep floors, and the article has nothing that says that TeX fails in any of its promises or guarantees.
In particular, the article's 'failures' of TeX are for, say, LaTeX or something contrived about some printer down the hall.
The issue is not whether TeX is capable of the tasks it was designed to do. The point is that it struggles with the the tasks it is actually used for today.
"""So, here the author seems to have a 'dramatic issue' to grab the reader by the heart and/or the gut. Yes, 'writers' tend to do that."""
I find this line amusing. Are you supposed to be a robot, explaining to other robots what humans do? A writer wanting to grab the readers attention is a thing that needs to be explained?
"""Of course, strictly this "issue" is 100% total nonsense: The problems he listed are all about LaTeX which strictly just is NOT the same as TeX, that is, as in:"""
And that is just a pedantic excuse, that no one cares about. People don't use TeX itself (and, to prevent another pedantic detail, I mean the vast majority of people), people use LaTeX+TeX.
"""Because the guarantee was about the output of TeX which was just a file of type DVI (which abbreviates 'device-independent file'). The TeX I continue to use as my most important word whacking software continues to put out a DVI file and appears still to meet the guarantee."""
Yeah, "walk to the Alphatype" might no be part of the architecture, but assumptions about the computing era Knuth lived in were. Which is what the writer means. Assumptions like ASCII vs Unicode. B&W vs color printing/output. Font technology. Multicore processors not being available. And tons of other relevant stuff.
"""Second, even a little reading of Knuth's book above shows that it would not be easy to be given a change in the input and then to get significant computational savings by determining what fraction of the output can be saved and not calculated again. So, we calculate all the output again."""
Who talked about "easy"? The writer talks about BETTER.
Also, several typesetting programs do just that, i.e determine the fraction of the changed output to recalculate. InDesign does not process a 100 page file again to change the style of one word in a paragraph.
"""Not due just to using TeX! However, TeX does permit writing to a file and reading from a file. So if want to use such file writing/reading to generate, say, cross references, then will need to run TeX more than once. But the effects of such writing/reading are due to the user and not to TeX. In particular, we can notice that in Knuth's book, there are no cross references that would require running TeX more than once."""
And that's relevant how? We care about how WE USE TeX/LaTeX and what WE WANT from it, not how Knuth describes it/uses it in his book. And our use includes cross-references.
"""Or, as we can see from reading Knuth's book, it is not easy to know exactly where will be the break between one page and the next. Then it will not be easy to do cross references accurate to the page number. So, in Knuth's book, he didn't."""
Again fail to see the relevance of this. Are we supposed to be content with what Knuth DIDN'T DO?
You make it sound like "page number accurate references" are outside the spirit of TeX, and we shouldn't ask for them.
Well, we want them, some of us need 'em, and it's perfectly reasonable to consider a lack of them, or the need for a two-pass phase to have them, a lack of TeX/LaTeX.
You only prove the writer's point.
"""I am sure Knuth saw this issue but wanted the high quality page breaking more than some automated cross references."""
For all your "rationality", you just keep sounding like you worship Knuth as a god that couldn't be faulted, and there can be no real problem with TeX's design.
Well, Knuth was a major academic, a damn fine algorithm scholar, and a very good programmer. Infallible? Hardly.
"""For me, I would reject that assumption. That is, absolutely, positively I do NOT want TeX to have an 'interactive interface', to be 'what you see is what you get', or to do word whacking for each of my keystrokes. I do NOT want such things."""
Good for you. Others want such things, as seen by the popularity of "see your output as you save" editors, and software such as Lyx.
Because the batch workflow suits you, doesn't mean it has to suit everyone else.
"""I would agree with the author that TeX does not bake bread, drive a car, vacuum the carpet, recognize human speech, do the calculations for computer generated scenes in movies, etc."""
Oh, got you! Here you seem to use irony to grab the reader in your favor. Yes, 'writers' tend to do that, but I wouldn't expect it from you!
"""Instead, TeX was mostly just for what Knuth said it was for, "beautiful books", especially ones with quite a lot of mathematics. Moreover, implicit was that tbe books would be essentially in English."""
Yeah. And in 2011, some of us perceive those as inefficiencies, and want a better-TeX that is not "just for books", not just for "mathematics" and not "essentially in english".
Your "but it wasn't designed that way" is NOT a counter-argument to what the writer says.
I think Knuth originally envisioned a writer working with a book designer/TeX developer to build a new set of macros for each project, and once the book was written the macros would be left alone. Therefore it would be very important to avoid breaking old macros, meaning TeX's behaviour needed to be nailed down. Today we would more likely take a PDF-like approach, specifying the file formats and using multiple programs to generate and process them.
I don't know about you, but I don't want the world to be "good enough". I want it to be better. We could accept all of what we have today, and take it for granted, and we'd live with it forever. But that would suck.
Even the most entrenched technologies can be displaced, or even replaced, with enough ingenuity, effort, and a superior technology. Most changes are happening slowly, as they must when we have billions of "installs". Most won't replace their predecessor completely, but erode it slowly:
IPv4 to IPv6.
Windows to OS X.
SOAP to REST.
XML to JSON.
HTTP to SPDY.
IE to Chrome.
Flash to Canvas.
Those changes didn't happen automatically; people pushed to get those new ideas out there. Truly better software will make it, but it won't happen if you accept that the old guard is here forever.
Forever is a long time.
One more thing: Many things that are really old — Unix, for instance — aren't the same as they were before. They've evolved, changed, and grown as developers evolve the software. Emacs today is tremendously different from its first release. Software evolves, and often dies when it doesn't.