The &lt is the less than sign.The &gt is the greater than sign.
html is a lot different than c or c++, thomas. there are no functions, if you want something to happen a few times in different spots on the page, you just gotta rewrite the code.
Not with HTML, but it's possible with CGI (if your ISP/host would give you CGI execution privileges). You could use C, C++, Perl, or whatever your ISP/host allows you to use to display the main page and then insert the other HTML file, text file, etc. or just parts of it. This is useful, say, to parse another page that contains frequently updated info (like stock prices) and insert it neatly into your own page.
If you thinking of showing HTML code on your page,try XMP tag, example. Tags are ignored until it closes, so be careful! If you are talking about files, check if you have "Server Side Includes". If you do, search for a tutor. You can "include" files almost exactly like C.
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