1. what's in this lecture
This lecture introduces you to a new "web technology" known as JavaScript. JavaScript is a kind of very simple programming language which most - though not all - browsers understand. Often it has a similar appearance to HTML, but it is in fact a different thing altogether. Instead of marking up text, it passes instructions to the browser which can make other things happen on the screen, or change the size of a browser window, or even close a window or open a new one. Many examples of this will come both in this virtual lecture and the associated online teaching materials.
There are two main methods of incorporating JavaScript on your pages. The first is through coding what are known as events into your tags. These give the browser simple instructions along the lines of, "when X happens, do Y". We will look at these things first.
With more complex tasks, you may need to use what are known as scripts, or simple programs, which give the browser a series of instructions rather than just one. Often you can make use of scripts written by other people, and this lecture will tell you how to do so.
At the very end of the lecture I will give you some initial pointers towards the Advanced Web Techniques course work and what is expected of you in that assessment.
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2. what JavaScript is
JavaScript is a simplified version of the programming language Java. This is itself a version of the language C. Java has certain inbuilt security features which make it ideal for use on the WWW, but it is a "proper" programming language and to use it properly requires a lot of study and an understanding of programming principles.
Do bear in mind that this course can only take you so far. This applies not only to JavaScript but other advanced techniques we will cover in this option, such as forms. Web design is something to which an entire degree can be devoted (and is, at Leeds - it's called the BA in New Media) but we have only one option and one semester to introduce you to a wide range of technologies and principles.
So I make no bones about the fact that this is an introduction to JavaScript and no more. It will discuss the basics, show you some possibilities, and then explain where you can go to find out more about it all. Some of you will have your appetite whetted and some of you will think it is just a frippery of no further use to you - either attitude is fine, but at least by the end of this lecture, you'll be able to recognise JavaScript when you see it.
A final note - not every browser can use JavaScript so never make a web site dependent on JavaScript for it to work. It can provide some extra padding and visual oomph to a site, if used well, but important information should be presented in plain, simple fashion.
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