Newbie questions:

Trying to write a web site that uses php and mySQL. Some stupid questions that my php book and looking through online docs didn't answer for some reason: 1. The website allows people to create projects. Each project's URL should be of the form www.domain.com/projects/project_name/index.php. So I guess php would have to create a project_name directory containing project pictures, files, etc, when the project is created. How in the world can I make it do that? 2. The website displays user-submitted news items stored in mySQL. Each news item can optionally be associated with a project or a project event. So if I wanted to go to a news item directly, I would go to something like www.domain.com/news/news_item_name. How do I get php to create the file news_item_name when the news is fetched from a database? And I still want everything to be searchable (eg, find all news items containing search string from project name). 3. Functions don't have defined to be on the same file as where they're called, do they? How can I tell php that a function in on another file? 4. Classes and variables aren't remembered through different pages, are they? Would I want them to be remembered through different pages? 5. And just making sure: if two people access the same web page that is generated by a php script, there is a seperate instance of the variables for each calling of the script, right? Thanks in advance, Gerry