HTML might seem like a simple language for web documents, and to
an extent, it is - that's what it was intended to be. If you
know what you're doing, though, you can do a lot more with HTML
than you might think. This article should give you a few ideas
on how to take HMTL further.
Inserting Multimedia Content
Plain text and graphics are all well and good, but sooner or
later you're going to want to insert some multimedia content,
such as a Flash movie, or an audio or video file. Unfortunately,
browsers don't handle these things themselves - they use
plugins, and you have to know the code to activate these
plugins. While this should be simple, it isn't, for various
historical reasons.
To begin with, there are two ways entirely different ways of
calling a plugin. Newer browsers use the object tag, like this:
That one's for Flash. To insert things like Quicktime or Windows
Media players, you just need to find out their classid and
codebase URL, as well as which parameters (param tags) they
require. Most browsers now support the object tag, but some
still use the embed tag instead:
For most cases, you should include both - it's best to place the
embed tag inside the object tag, as this will cause browsers
that understand object to ignore your embed. As an extra
fallback, you might want to insert a 'plugin not found' message,
with a link to allow users to download the plugin, but in most
cases browsers should now do this for you automatically.
For Internet Explorer only, you can extend object tags to call
plugins that are on your server instead of on your computer -
this is known as 'ActiveX'. Its most common use is to let users
install web-based programs such as instant messengers without
having to download and run a standalone install program.
However, you have to realise that many users will see ActiveX as
dodgy, because it is an often-used way of installing undesirable
software, and people who aren't using Internet Explorer just
won't see anything at all. If you're designing a site for a
limited set of users, however (such as an intranet), ActiveX can
be a very powerful capability.
Tables
Even though tables are rarely used for layout any more, they're
still used for what they were originally intended for - actual
tables of information! You'll probably need one at some point,
but they're still as complicated as ever, so it's good to take a
while to learn about how they work.
Basically, to create a table, you have to create the rows and
columns individually: each table tag contains row (tr) tags, and
each tr tag contains column (td) tags. A typical table looks
like this:
month
sales
January
200
February
300
This can be a difficult way to work, especially if your data is
organised in columns, not rows. You just need to remember that
the data you put in the tds will line up depending on their
order in the tr: so, for example, 'sales', '200' and '300' will
line up in a column, because they are all in the second td tag
of each tr. You might find it easier to use tabs instead of
spaces to separate the tds, so the table appears lined up in the
HTML the same way it will on the page.
Once you see how that works, you pretty much understand tables -
wasn't so hard, was it? The only thing left to realise is that
you can make one td fill more than one column using the
'colspan' tag. In the example table, for example, you could add
text that fills two columns by adding this row:
text
Experiment a little, and you should be alright. Good luck.