How do I add a sub-url to a url?

I've been ashamed for a long time that I have no idea how to do this. If friends and family members who routinely call me to help them fix their computer glitches only knew about this ignorance, they might just reconsider asking me to help them the next time around. Now that I think about it, maybe that isn't a bad thing.

Anyway, can someone explain how to insert a sub-url into a URL. For example, I want to refer to a discussion in one of the RPGWatch forums and I want to create a link and when the person clicks on it, it takes them to the thread, and to a specific point in that thread. My God, how do I do this? I feel so... so... naked and ashamed.

See there's a "#1" to the right of your post? That's the link to specifically that post:

However, that'll only show that post, i.e.no others

To show the thread, but go to a specific post, you need the "showthread" variant.
i.e. this change the "showpost" part to "showthread" and keep the same post ID:

Another example, Dart's post that says "They deserve all the praise and support they can get, in my opinion."

Post only:
http://www.rpgwatch.com/forums/showpost.php?p=1061368458&postcount=3
Note: you can leave off the "&postcount=" part.

Thread with that post focussed:
http://www.rpgwatch.com/forums/showthread.php?p=1061368458

Lastly, if you have a link to the thread (based on a post ID) and you want a *different* post highlighted than the post that the URL is pointing at, add "#<insert post number here>".

For example, Dart's post has a post ID of 1061368458 and is post #3 in the thread, but you want to focus on #5.
You can do the following:
Which basically says "render the thread page with this post (ID 1061368458) on it, but focus on the post which has '5' as the name of its link". This will only work if the thread is rendered with that link visible. Adding "#22" will not work, as it is on the next page, and will result in sending you to the top of the page instead.

Blah blah, sorry for the spam. Over and out

Wow thanks for all that information! I will have to study it all now...