What is the difference in a style a skin and a template?

[rootsxrocks]

Ok first Im not a total Idiot I do have a basic concept of the meaning of the terms, but I am confused about, what to look at first and the order to install it. the number of passwords I have created in the last week has my head a little sore , I need help, and I would be glad to answer any Horticultural question in exchange for your time.

I have my basic install done and I want to ad vbcredits and games, both sets I believe arcade Pro and vb gaming, I like the random picture show on the cover of this forum http://www.mercuryserver.com/forums/index.php? and I like the dark colors for the arcade.

But I want the forum to be much brighter, yet warm and homelike, sutle green and toast like colors with a white fourm and black type.

I need a little room for ads but I want to make it a pleasent place for the members first.

so, if your still with me are these seperate things or sets of the other? templates skins and styles, which should take priority?