Okay, the question is a bit vague, so the answer might seem a little vague too.
Let's have an example to help visualise. You have a newspaper website, so you serve lots of articles - but all from one dynamic page...
/articles.do?Article=Important-News-Item
/articles.do?Article=Cash-Strapped-Business-Goes-Into-Administration
And so on.
You then add some .htaccess (mod_rewrite) love to the site...
/Articles/Important-News-Item/
/Articles/Cash-Strapped-Business-Goes-Into-Administration/
And you rewrite those URIs back to the articles.do page.
So in your articles.do page, you use the request string (Article=Value) to query the Article table and get back the relevant page...
SELECT
Headline,
Content,
Image
FROM
Article
WHERE
RestfulId = 'Important-News-Item'
And then you pop that onto the page.
Shout if I've missed the point on this question.
mod_rewrite example
This is the mod_rewrite rule for the example above, it maps the restful URI back to the articles.do URI.
RewriteEngine on
RewriteRule ^Articles/([^/\.]+)/?$ articles.do?Article=$1 [L,NC,QSA]
The easiest way to explain this (not the technical way to explain this) is:
1) The first bit (^Articles/) looks for any address that starts with "Articles/"
2) The second bit (([^/.]+)/) represents "Whatever comes between the "/" after Articles and the next "/" after that, which in this example is the title of the article.
You can capture more parameters by adding more "([^/.]+)/" segments to the end...
RewriteEngine on
RewriteRule ^Articles/([^/\.]+)/([^/\.]+)/([^/\.]+)/?$ articles.do?Article=$1&$2=$3 [L,NC,QSA]
In this example you could convert
/Articles/Important-News-Item/My-Key/My-Value/
into
articles.do?Article=Important-News-Item&My-Key=My-Value