A website is just any size of collection of files on a server. If we’re talking about the website covered under the domain name TechDonkey.com, all the techdonkey files will be sitting on that server. Webpage files here, graphics here, mail over here, web scripts here, and so on.
Think of the server computer as the house the website lives in, okay? If the domains are small, or the server has lots of space, many websites can live in the same server (kinda like an apartment building with lots of tenants.)
Domain names and websites ain’t always the same thing.
ElaineMiller.com is one domain name and one website.
KAP.VancouverLeather.com is one whole complete website under a subdomain of VancouverLeather.
Your internet service provider (ISP) will often give you a few MB free web space in a subdirectory. It usually looks like: http://yourisp.com/~yourusername/
Sometimes a company’s site is very big, or has very different arms of business, so it splits up into a few domains.