Restricting HTML pages to certain groups?

I'm sorry if this is in the wrong place.

I Have 2 pages. 1 for one chat box, and one for the other chat boxes. I don't want the other members finding this chat. There are 2 groups, who i don't want them leaking information to. How do i do this?

Also, How to I make a page "Members Only" So that if you aren't registered, if you just click the link you cant see it.

I also face a similar dilemma. How can I make it so that random visitors can't visit one of my custom HTML pages?

I am not sure about the coding for this, but what I did was create my pages, then create some buttons with the same name as the pages. Then I created a widget and set the permissions to members only. Then I added the HTML I wrote into the widget using the buttons I created to link it all together. One other thing is to now make the HTML pages public. Use the links in your ACP as links to the pages.
Hope this helped.

sweet. I was actually thinking about writing javascript to confirm log in before access. Thx, NOT SOLVED! Just aided.