how do I execute a customize script after document loaded?

pengdw <[email protected]>
Newsgroups gmane.comp.mozilla.devel.dom
Message-ID <[email protected]>
How do I insert some script in the document, works like a <script> tag?
lmpx.com only provides a reader for public news (NNTP) servers. It is not affiliated with the servers or forums shown here and is not responsible for the content of articles, which is written by their respective authors.