Using java script on your website
Java supplements HTML code
with
little programs that do specific things. Java script is mostly used for
special effects, such as the scrolling clock that follows your
cursor around (if you are viewing in Microsoft Explorer, but maybe
not if you're using another browser). There are several other cool
things you can do with Java, but there are drawbacks. The first
problems you'll encounter with Java special effects is slower page
download time.
HTML is the standard. HTML code
has been used for web pages since the start of the Internet Age. For
you kids born in the 1980s, it's been around longer than you, which
is why some of you probably think of it as an old fuddy-duddy way of
coding web pages.
HTML is great for creating "static" pages
-- pages that let you read them like you would text on paper. It
will also let you illustrate that text with "static"
images, and it will let you do nice layouts of a web page using as
much color as you want. But, that's about it. HTML is the basic tool
for web content that doesn't move around on the page, that is static web
pages.
Of course, someone decided to solve
the "static problem." First came animated GIFs, then came
Java. Since they came first, we will discuss animated GIFs before we
jump into hot Java.
 |
Animated GIFs. The spider on the left
is an animated GIF. GIFs are limited to a 256 color pallet,
hence they usually look like drawings rather than photos. An
animated GIF is actually several images saved in one file.
When loaded onto a web page, which is done by embedding the
animated GIF like any other image, the browser simply loops
the images.
If the spider moves up or down in a dozen
small movements (each a separate image), then the animated
area of the image is saved 12 times, one for each movement.
The image has to load 12 times to make the animation loop.
 It doesn't take a lot of animation
to make a large, slow loading, image file. It doesn't take a
lot of animation to drive a visitor away. Especially if
you're showing animated Santas at Easter or animated bunnies
at Christmas.
|
Java Applets. If you want something bigger or
a more sophisticated animation than a spider dropping or a
toe-tapping Santa, say something like the swirling calendar/clock
that follows your browser around the top of the page, you'll need
Java script to create the animation. Animated GIFs simply loop
images in a predefined order; they do not support interactivity with
the person viewing the web page. All you can do with the spider or
the Santa is watch them dance in the same spot on the screen,
whereas you can move the calendar/clock by moving the cursor around
your screen.
Java is a programming language developed by Sun
Microsystems in the 1990s. Programs written in Java are called
applets. Browsers built before the mid-1990s do not run Java
applets. Java can do great things, but it's not supported in all
browsers, at least not without downloads or upgrades. Older browsers
often do not have the ability to interpret the script correctly or
debug the errors it perceives.
Another problem with Java script is that if you have
more than one script running on a web page, they may do battle and
neither will work. Even though most browsers in use today can handle
Java, people have to adjust their browser's Internet security
options to run them. So, people afraid of getting a virus or being
hacked can, and often do, turn off the ability to run applets in
their browsers or never download the plug-in. Further, Microsoft
has announced that it will no longer support Java in its browser
after 2007.
Given all these drawbacks -- slower page download
time, possible viewer annoyance, and they may not work because the
viewer is using a browser which doesn't support that feature --
consider whether it's worth the time and bother and cost of using it
on your website.
Flash. If you want to be able to control the
animation of your special effects, that is, have the ability to make
the animation stop and wait for the user to click a button to start
it again, or you want it to have a video movie quality animated
presentation to wow your website visitors, then you need Flash. We talk more
about Flash here.
Email info@oakridgewebdesigns.com
if you have questions on this topic.
To Java or not
to Java?