Add a template into a template?

[loonytune15]

Basically I have a sidebar on my forumhome, and what i want to do is add in an affiliates section.

but instead of having a huge list of affiliates in my forumhome template, I want to call in another template that has all the information in it.

Like having $affiliates and calling to an affiliates template.

How do I do this?

Sorry if this has been posted but so far I haven't found anything that i understood ho to do..