#100DaysOfWeb in Python Transcripts
Chapter: Days 5-8: HTML and HTML5
Lecture: A little HTML history
0:00 Before we start writing some HTML
0:01 let's just talk briefly about its timeline
0:04 when it was introduced, and what features were added when.
0:08 HTML starts way back in 1990, 91, with Tim Berners-Lee
0:12 where he invented HTML back at CERN.
0:15 And it was really meant to just be linking documents.
0:18 All right, so that's kind of how it started.
0:20 Hyperlinks, basic non interactive documents.
0:24 In 1995 to five years later
0:26 HTML 2 was released and that added form elements
0:29 such as text boxes and option buttons.
0:31 Ability to change the background
0:33 and better tables and things like that.
0:36 We quickly get to HTML 3.2.
0:39 There was, you know HTML is very standards driven
0:42 and they tried to do some stuff for HTML 3
0:45 and apparently that failed or didn't go anywhere.
0:47 So they rebooted that effort as HTML 3.2.
0:51 And here we have better supports for tables still.
0:55 Applets, text floating around images, things like that.
0:58 Superscripts, subscripts.
0:59 So still working on this document
1:01 in this non interactive like document world.
1:05 Moving ahead quickly now.
1:06 In 1999, remember this is the Dot Com boom.
1:09 Pets.com and all that craziness.
1:12 We get HTML4 and finally we get style sheets.
1:15 So until then, you wanted to style something
1:17 you would have to put the styles on the elements.
1:20 Think how tedious that must have been, right?
1:22 That was horrible if you wanted to have
1:24 a common design across your whole site.
1:26 So here we have style sheets
1:27 that allows us to style all of our site
1:29 not just embedded in each individual page
1:32 and scripting ability for multimedia elements.
1:36 Sort of a competitor to HTML4 is XHTML.
1:41 So HTML4 is a little bit more loose.
1:43 It doesn't have to be an exact super set of XML.
1:48 And remember around the 2000's
1:50 this is like the height of XML on a text base.
1:53 We have XML SOAP web services, all sorts of stuff like that.
1:56 We have style sheets, XSSLT, transforms
1:59 all those kinds of things for XML.
2:01 So there was a push to take HTML
2:03 and make it proper parsable XML, all right?
2:06 Everything is properly closed.
2:09 You know that got some traction
2:10 but really modern day HTML is not nearly that strict
2:14 and it's probably a good thing.
2:17 However, we've been moving pretty quick up til here.
2:19 In 1999, 2000, we get these two competing standards
2:23 and then there's a long waiting period.
2:26 As time goes on and on
2:28 all the way out to 2014.
2:33 In 2014, HTML5 comes along.
2:36 That was a long period there
2:38 of not too many things being released.
2:41 This release of HTML is meant to replace things like Flash.
2:45 Remember Flash, you had to have Flash to watch this video.
2:48 Well replace those types of things
2:50 with built-in video elements and audio elements and so on.
2:54 Also allowed for web applications to be much more like
2:56 well, applications and not documents, right?
2:59 They can access local storage, the little databases
3:02 they can run in offline mode, all those kinds of things.
3:05 They have location based services, mapping and whatnot.
3:08 And also changing the syntax a little bit
3:11 to separate content from presentation.
3:13 When you look at some of the features
3:15 especially around validation and stuff of HTML5
3:17 you will see it's decidedly not an XML document, all right.
3:21 You might have attributes that don't have values
3:23 and things like that.
3:24 So this is more of a carrying on
3:26 of HTML4 heritage than the XHTML.
3:28 So basically 15 years between major new versions here.
3:33 But now we have HTML5
3:35 we're kind of moving along
3:36 to building real applications on the web properly.