Q: Why do some of my modules appear on multiple pages?
A: Each page in your site uses a page template that determines the layout of the page. Typically, multiple pages on your site use the same page template. In these cases, any modules that are added outside the main body section of a page will also be added to the other pages that use the same page template. This is to make it easier for users to add content to multiple pages on their site.
For instance, in a Two Column Left page template, by default, you have the header, navigation bar, splash image, a narrow column on the left, a wide column on the right, and the footer and disclaimer sections at the bottom. Modules in every section of the page template except the wide right column will appear on each page that uses this page template.
If you want to add a module outside the main body section (or outside the wide column if you're using a two- or three-column page template) of a single page, then you should create a new page template and apply it just to that page. Take a look at our tutorial on how to create a new page template.