There are two major ways to redirect a browser to another web-page:

First out we have the <meta>-tag: This line, when placed in the HTML-document's head section, will redirect to picturesofmydog.html after three seconds.

Then, there is the JavaScript version: This would do an immediate redirect to the dog-page. It's pretty simple to insert a delay using JavaScript's setTimeout() function if desired.

But... please, plEASE, don't redirect just because you can do it. Everyone hates redirects, and I'm sure you do that too, right? They do have their uses, but in most cases a server-side include, PHP trick or a link would do just as good. The node at HTTP meta-equiv has some words on what to do and not do.