What is a Web-page?

 A web-page is a single "screen" containing information on the internet. The length of the page my vary, depending on the contents of the page, but is generally less than about 2 screen-full's and may require "scrolling" up and down the page, or screen.

If you can imagine a piece of paper, as analogous to a web-page, it's blank and can contain anything you might choose to put on it. If you have 2 pieces of paper, you have 2 web pages. If you want to put more information on a single page, then you might need to take another piece of paper and tape it to the bottom of the existing piece of paper, thus lengthening the page. In this way, a single web-page can go on and on and on, and still be considered a single "page".

Another unique aspect of a "web page" is that it has a single website address. If you pay close attention to the address bar, at the top of your browser, you'll notice that each page's web address ends in a descriptive word or phrase. 

More "technical" information: Wikipedia: Web Page