It is possible to clump together a chunk of HTML, stick it in a ‘master file’ and call it up on my webpage instead of having to rewrite the HTML for that object every time it appears on the page?

http://www.candsdesign.co.uk/articles/coding/includes/

Server Side Includes

I use php. The format is:

PHP Code:

<?php include 'wherever/whatever.inc'; ?>

The included file should not have a header, title or anything like that, unless it is needed(for example including a common header). It can be HTML, Javascript, or more php code.

Oh wow, thank you very much! This makes my life much easier now.

Now, in the instance I’m using SSI for a button (or anything else really), how would I apply different text to the button each time it’s called up?

For something like that I would use a function

I’m not really understanding what you mean by use a function with SSI. I’ve done some browsing around and none of the tutorials and guides that I’ve read have made any reference of functions in relation to SSI.

Could you please explain?

You don't actually make a function in SSI. You include a file that has the code to write out the required HTML.

eg:
To write a button that changed (as buttons do) captions etc:

<%
sub writeButton( sType, sName, sID, sValue)
dim quotes
quotes = chr(34)

with response
	.write "<input "
	.write "type="
	.write quotes
	.write sType
	.write quotes
if sID <> "" then
	.write " id="
	.write quotes
	.write sID
	.write quotes
end if
if sName <> "" then
	.write " name="
	.write quotes
	.write sName
	.write quotes
end if
if sValue <> "" then
	.write " value="
	.write quotes
	.write sValue
	.write quotes
end if
	.write ">"
	.write vbcrlf
end with
end sub
%>

And to use it you pass the required parameters

<%writeButton "submit", "go", "go_btn", "Go Here"%>

that example would write on to the page;

<input type="submit" id="go_btn" name="go" value="Go Here">