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Half Duplex
Twenty years ago, modem communication was either asychronous full duplex (one character at a time sent in both directions at once) or synchronous half duplex (a block of characters at a time, but sent in only one direction). These days, modems are all synchronous half duplex. Why? Because it's more efficient: at 28.8 kbps, 2 modems can send and receive 25 packets of data every second. That looks like duplex transfer to a casual observer, but if you're counting in milliseconds, the duplex is only half full.
home page
Web sites are by nature tangled groups of interconnected pages. To make them easier to navigate, the sites have one or more home pages that you can use for orientation. A home page serves as the site's introduction, starting point, and guide.
HTML
Hypertext Markup Language
As its name suggests, HTML is a collection of formatting commands that create hypertext documents--Web pages, to be exact. When you point your Web browser to a URL, the browser interprets the HTML commands embedded in the page and uses them to format the page's text and graphic elements. HTML commands cover many types of text formatting (bold and italic text, lists, headline fonts in various sizes, and so on), and also have the ability to include graphics and other nontext elements.
Development and maintenance of HTML standards is coordinated by the World Wide Web Consortium.
Hyperlink
Hyperlinks are the easy-to-spot underlined words or phrases you click in World Wide Web documents to jump to another screen or page. Hyperlinks contain HTML-coded references that point to other Web pages, which your browser then jumps to. Also called anchors