He says several times that JavaScript succeeded in spite of being a bad language because it was the only choice. How come we're not all writing Java applets or Flash apps?
Well, about ten or fifteen years ago, "we all were" would have been the answer. Except that back then, there were multiple choices -- plug-ins meant you could choose Java, or Flash, or ActiveX (Visual Basic 6, anyone?), or VRML for that matter.
The number of security issues that plug-ins have had in the last two decades makes most of them non-starters nowadays, although there are still plenty of sites that use them extensively (say, Childrens' game websites like Neopets and Nick Jr.'s website) depending on the target audience.
There were other advantages. To write JS you just need a text editor, and it's easy to pick up. To write Flash requires spending several hundred dollars. To write Java requires the JDK and to learn Java.
Especially on 1995 technology, that mattered. Compiling Java took a while. I didn't use Flash enough to retain an impression of speed, but it sure wasn't instantaneous.
It's also the reason why Flash was so prevalent until recently and is still installed in 90-something % of desktop computers: it's faster. Significantly faster, and very specially so in the 90s and early 2000s.
Used to to do a good amount of flash development - you could actually do it with just a text editor and a compiler (which was free). There were also quite nice free IDEs, like FlashDevelop.
If I had to pinpoint it, I'd say Flash's primetime was around 2005-2008 perhaps, and FlashDevelop was available then. Guess we probably define it's prime differently haha, I'm thinking more of when it matured - AS3 as a language, lots of tooling choices, etc.
I wasn't ever anything close to a professional Flash developer, I'll take your word for it if you say that was the best time to be developing for it.
I was thinking about the days of Homestar Runner, Weebl and Bob, Newgrounds, and so on, when flash cartoons and games were (for kids, at least) a huge part of internet culture, and everyone wanted to be a Flash animator. Youtube kinda killed the Flash cartoon medium, sadly. Sure, videos are simpler and don't rely on a proprietary binary blob, but there's nothing like loading up a Strong Bad email and clicking random things (or, uh, holding down tab) trying to find secrets.
or VBScript for that matter.. I think there's some confusion about why JS won. JS couldn't easily manipulate the DOM either until JQuery in 2005-2006.
The fact that Java, ActiveX etc.. had full control of the system and causes problems ensuring security was an issue, but it is not the reason why JS beat them all.
Don't discount the power of 1) free and 2) easy to use software that is 3) not controlled by a single corporation. JS is the only web programming language that is all of these.
Yea, maybe Python or Clojure in the browser would be cool. I would argue Clojure is absolutely more difficult for a novice to learn, and Python provides what additional benefit? JS was there first.
The only reasons why plugins existed is you couldn't do these kinds of things in the DOM. JQ, and the subsequent advances in browser technology, HTML, CSS, JS - made it so you can. Also, other things being equal - programmers will choose elegance over bloat, less layers of abstraction over more. Plugin architecture became just an unnecessary layer between the programmer and the browser, after HTML/JS/CSS caught up.
JS did not become ubiquitous by accident, or because it was the only choice. There were many choices (all being pimped by big well-funded companies). JS won because it was the better than the alternatives.
While security is the main answer, it was also that Java and Flash aren't necessarily available. That is, getting them to run on another machine was frequently a huge issue, especially if you tried to put in any kind of complexity.
Javascript, on the other hand, was omnipresent and comparatively accessible. It was the least bad option by a wide, wide margin. For a different comparison, I switched from Java applets to PHP in the early 2000s. I didn't really get into Javascript until many, many years later around 2009: before that, Javascript was mostly a way to make Flash work properly.
Oh, yeah, especially after Microsoft stopped shipping Java.
There was also the version issue to worry about. "Pardon me, Mr./Ms Customer/User -- would you mind terribly going and downloading and installing a 20 MB Java update on your 14.4k dialup connection before using this page?"
I always found it a bit hilarious how Sun, after getting Microsoft rather onboard the Java train, albeit with their necessary native extensions, decides to sue them and put an end to it. And promptly kills off Java distribution and adoption by the largest software developer in the world.
Even stranger is how Sun, a hardware/platform company, decided making a popular platform that's hardware and platform independent would help their business. Sometimes I wonder if there was a really well thought-out plan, or people were just doing things.
The "necessity" of those extensions is debatable, and they meant that code wouldn't be portable to Sun's implementation. There was real cause for concern, and there weren't a lot of other options for fixing it.
Sun probably also realized that they weren't about to compete directly with mighty Microsoft on platform lockin of all things, so they played a different game.
Flash still powers Youtube for most users, Silverlight for Netflix and Unity's plugin is required for most 3D games on Chrome's Marketplace (not sure where else to look for successful HTML5 games).
The number of security issues that plug-ins have had in the last two decades makes most of them non-starters nowadays, although there are still plenty of sites that use them extensively (say, Childrens' game websites like Neopets and Nick Jr.'s website) depending on the target audience.