<link rel="stylesheet" media="screen" type="text/css" href="/css/styles.css?v=8" />

The rel attribute provides metadata about the relationship of the link (stylesheet), media attribute tells us what the stylesheet is for (screen), the type attribute tells us it's "text/css", href tells us the Universal Reosucre Indicator (or Link) to the actual location of the stylesheet document (in this case located in a folder called css located in the root directory of the website). The "?v=8" in the URL string is a trick to make browsers grab the latest stylesheet from the server as opposed to from cache.

<link rel="stylesheet" media="screen" type="text/css" href="/css/en.css?v=8" />

This one looks like its an english-language specific stylesheet as far as I can guess - probably to ensure correct formatting (left to right, top to bottom) of content.

<link rel="stylesheet" media="print" type="text/css" href="/css/print.css?v=8" />

This stylesheet is used for printing - when the user prints the page to a printer, this stylesheet is used. Typically print stylesheets remove unnecessary graphics, navigation, or other stylistic effects that may negatively impact printing. So for instance a print stylesheet may remove background images, hide the navigation, and maybe even change the font color to optimize the page for best print results.

Hope this helps.

"styles.css?v=8" is simply the link to that site's particular stylesheet with a bit (?v=8) that forces the browser to grab the newest version of styles.css from the server (not generally necessary) in case the viewer has it cached in their browser.

Your website can use a .css stylesheet as well, if you like. CSS is very powerful for both design and layout of HTML pages and is definitely worth learning.

I personally use this site:

http://w3schools.com/css/default.asp

When I can't remember or need to find out how to make CSS do what I want. There are tons of CSS resources out there though, just look up "learn CSS" in google and you'll get  links to good resources.