1) Eric Raymond, compiler of The New Hacker's Dictionary, defines a hacker as a clever programmer. A "good hack" is a clever solution to a programming problem and "hacking" is the act of doing it. Raymond lists five possible characteristics that qualify one as a hacker, which we paraphrase here:

• A person who enjoys learning details of a programming language or system
• A person who enjoys actually doing the programming rather than just theorizing about it
• A person capable of appreciating someone else's hacking
• A person who picks up programming quickly
• A person who is an expert at a particular programming language or system, as in "UNIX hacker"

   Raymond deprecates the use of this term for someone who attempts to crack someone else's system or otherwise uses programming or expert knowledge to act maliciously. He prefers the term cracker for this meaning.

   2) Journalists or their editors almost universally use hacker to mean someone who attempts to break into computer systems. Typically, this kind of hacker would be a proficient programmer or engineer with sufficient technical knowledge to understand the weak points in a security system. For more on this usage, see cracker.

   A hard disk is really a set of stacked "disks," each of which, like phonograph records, has data recorded electromagnetically in concentric circles or "tracks" on the disk. A "head" (something like a phonograph arm but in a relatively fixed position) records (writes) or reads the information on the tracks. Two heads, one on each side of a disk, read or write the data as the disk spins. Each read or write operation requires that data be located, which is an operation called a "seek." (Data already in a disk cache, however, will be located more quickly.)

   A hard disk/drive unit comes with a set rotation speed varying from 4500 to 7200 rpm. Disk access time is measured in milliseconds. Although the physical location can be identified with cylinder, track, and sector locations, these are actually mapped to a logical block address (LBA) that works with the larger address range on today's hard disks.

   2) For a Web site developer, a home page is the first page presented when a user selects a site or presence on the World Wide Web. The usual address for a Web site is the home page address, although you can enter the address (URL) of any page and have that page sent to you.

   A number of Internet access providers, such as America Online, offer subscribers free space for a small Web site that is hosted by one of their computers. Geocities is a Web site that offers registered visitors similar free space for a Web site. While these services are free, they are also very basic.

   A number of hosting companies describe their services as virtual hosting. Virtual hosting usually implies that their services will be transparent and that each Web site will have its own domain name and set of e-mail addresses. In most usages, hosting and virtual hosting are synonyms. Some hosting companies let you have your own virtual server, the appearance that you are controlling a server that is dedicated entirely to your site.

   HTML is defined in practice both by Netscape and Microsoft as they add changes to their Web browsers and more officially for the industry by the World Wide Web Consortium (W3C). A new version of HTML called HTML 4 has recently been officially recommended by W3C, making this level an effective standard. However, both Netscape and Microsoft browsers currently implement some features differently and provide non-standard extensions. Web developers using the more advanced features of HTML 4 may have to design pages for both browsers and send out the appropriate version to a user. Significant features in HTML 4 are sometimes described in general as dynamic HTML.

   There are a number of helpful books on HTML. We like Laura Lemay's Teach Yourself Web Publishing with HTML 4 in One Week (Sams.net Publishing) and Ian Graham's HTML Sourcebook (John Wiley). However, it's possible to learn HTML from material available on the Web itself.

   The World Wide Web Consortium's section on Hypertext Markup Language is the best place to begin understanding the origin, history, and latest status of HTML.

   Essential concepts that are part of HTTP include (as its name implies) the idea that files can contain references to other files whose selection will elicit additional transfer requests. Any Web server machine contains, in addition to the HTML and other files it can serve, an HTTP daemon, a program that is designed to wait for HTTP requests and handle them when they arrive. Your Web browser is an HTTP client, sending requests to server machines. When the browser user enters file requests by either "opening" a Web file (typing in a  HTTP request and sends it to the Internet Protocol address indicated by the URL. The HTTP daemon in the destination server machine receives the request and, after any necessary processing, the requested file is returned.

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