Frequently Asked Questions



Cookies--What are they? CDs--How is recording done on a CD? Can they be repaired? Can I record my own CDs? File Extensions like .jpg, .gif, .sit and .zip--What are they? Webhosts--where can I find a free one? TCP/IP--? URL anatomy--

Cookies--a Quick Primer

A cookie is a small file stored on yourcomputer containing information that a web site can use to
identify your computer. Sites that create cookies can store information about your use of their site in
a database on yourcomputer. In one sense, they act much in the same manner as a salesperson in a store
you are visiting a second time who now knows your name, preferences, etc. When you return to the site,
the cookie on yourcomputer is used to find this information andto tailor your current visit based on
what you did on your prior visits. You may consider this an invasion of privacy, and in a sense it is, but some web pages will not
allow you access unless you will accept cookies. On sites where you are planning to purchase something
you may not be able to do so if you have your cookies turned off. Keep in mind that any information you provide to a website--signing a guestbook, giving your email
address, etc., --is stored somewhere and huge files of these bits of information are sold and may be
used by agencies to send you annoying email ads.... Once on such a list it may be impossible to get off
and the junk mail keeps right on rolling in! How do I turn off cookies? Look in the "Help" area for your particular browser to learn how to control cookies on your computer.
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CDs: How is recording done on a CD?

A CD, or Compact Disk is actually a complex sandwich of several different materials. The bottom part,
which gives the CD its strength, is a disk of clear plastic. On top of this is the recording layer made
of an organic dye laid down as a continuous spiral (22,188 revolutions, to be exact) extending over 3.5
miles!!! The spiral acts as a "groove," guiding the recording laser along its path from the inside of the
disk, to the outer edge. This "grove" can contain over 640 MB of data. On top of this layer is a very thin
layer of reflective metal, usually of 24K gold or silver-colored alloy. Topping this "reflector" is a
clear lacquer coating that protects the upper layers from damage. Then comes the label. So there we have
it: 5 layers in all. To do the recording, a laser, located beneath the disk, burns a series of "pits" into the dye spiral.
The intact(unburned areas) portions of the dye between the pits are called "lands." It is this pattern of
pits and lands that makes up an exact representation of the binary data, the ones and zeros making up the
digital information to be copied. In "writing" information on the disk, the laser shines through the clear plastic to the dye above and
burns a pit in the dye. The spot becomes opaque due to the burning. Lands, however, being untouched by
the laser, are transparent. A CD player (as your computer's CD ROM drive) uses a laser to read and translate this series of
alternating dark and transparent spots back into a series of ones and zeroes (binary data) which the
computer can use. So it's like this: Laser light passes through each transparent Land, strikes the thin
metal reflective layer above it and bounces back through the plastic to the CD reader's sensors. All this
happens very quickly and more than 24 million readings can occur every second. Can a CD be repaired?
Well, yes and no. Scratches will inevitably appear on your CDs over a period of time regardless of
how careful you are. Scratches to the top--or label--side of the CD which extend down through the dye
(data layer), disrupt the continuity of the organic spiral and destroy data, thereby eliminating the
possibility of the disk being read and thereby rendering it useless. You might as well toss such a disk
in the trash. Scratches in the clear plastic bottom side of the disk cause the laser beam to be difused
so the sensors cannot read the date, causing the disk to have read errors-to appear unuseable. However,
if the scratches are not too deep, the plastic can be polished with a fine rouge in a liquid base
available from several companies. I have done this several times, resurecting disks that would otherwise
have to be discarded. Can I record my own CDs?
Both external and internal CD burners are now available for both PC and Macintosh computers at a cost
of from below $100 to --well, whatever the market will bear. Newest Macs ship with them. In my opinion,
if you pay more than $300 for one, you are throwing away your money. You should know that you can buy CDs
that can be written to one time, called CD-R disks, (about 20 cents each or less when bought in
multi-packs) and CDs that can be written to and erased many, many times--called CD-RW disks (about $.90
each when bought in multi-packs). This makes the CD an excellent and very inexpensive method of doing
backups a way of sharing data with others!
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File Extensions like .gif, .jpg, .sit, .zip...what are they?

Unless you live in a cave, you have undoubtedly come across files with these extensions added to
their names. Their purpose is to identify the file type. .sea files are self expanding archives created
by one of Aladdin's Stuffit Compresson applications and these files self-expand to become useable all by
themselves. .sit (StuffIt) files have likewise been compressed by one of Aladdin's StuffIt compression
programs. These normally require that you decompress them, easily accomplished with the drag and drop
program StuffIt Expander, a free application available for download online at
Aladdin Systems, Inc. Another common compression file is the .zip file, popularized on the Microsoft Windows platform but
also now used on Macs as well. These files are also decompressed with StuffIt Expander simply by
dropping them on the Expander icon. .hqx files are BinHex encoded files (BinaryHexadecimal), converted to a textual format to make the
transfer over the Internet more reliable. .bin (MacBinary encoded) files retain their pure binary code
and take up less space than .hqx files. Both types are easily expanded with Aladdin's Stuffit Expander. "Why are files compressed?" you ask. I won't get into compression schemes here but will just say
that it takes much less time to transfer small (compressed) files over the internet than large
(uncompressed) ones. Simple as that. It makes them more easily transmitted in terms of time. JPEG (Joint Photographic Experts Group) files, now known as .jpg files are a fraction of the size
of the originl graphic file, and are easily viewed by simply dropping them on virtually any open browser
window as well as a myriad of picture viewers and graphics programs. .gif (Graphic Interchange Format)
files can be animated and represent the preponderance of cutsie little moving things you see on webpages,
such as the FAQ thingy at the top of this very page. You can actually just grab it with your mouse and
drag it out of your Netscape browser onto your desktop and Voila! You how have your own little .gif to
drop into your email program--assuming you have an email client such as AOL uses, or Netscape mail, for
that matter. Hey, try it right now. Drag the FAQ .gif onto your desk top, and then drop it back onto
your Browser and watch the show. The .tif (or TIFF, Tag Image File Format) format is an uncompressed format developed in 1986 by a
committee trying to determine a standard for high-quality digital images. TIFF images are commonly used
in publishing and tend to be very large. There are well over 60 other file formats extensions that you may run across, but the above are
likely to make up the bulk of what you will commonly see attached to your files.
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Where can I find a free or Inexpensive webhost for my website?

There are many sites which offer you space on their computers to place your webpage/site. Do a
search, friends. That's what
Search Engines are for! Some offer as much as 100 MB of storage space as long
as you allow them to put an ad or banner at the top of your page. A fair trade off. Just look at this
page. Is that ad/banner too obnoxious to put up with in exchange for free storage space on someone else's
computer? FYI, 50 mb of space is one humungus amount of space! Please remember that no question is stupid
if it is sincere, so if you do have a question, email me!
Here are a few of the free webhosts that I currently use: Alta Vista Look around for the free area. Angelfire.com Offers 50MB FREE Space AOL Members only website hosting FortuneCity.com Offers 20 MB free space. FreeYellow.com Offers 50 mb free space Geocities.com Offers 15MB free space gURLpages.com Offers 10MB free space Homestead.com Offers 16 mb storage. Tools for site building. Good novice host. Hostway Domains for 6.95 as well as inexpensive hosting. My Family.com Free Webhost Tripod.com Offers 50 MB free space. And there are free ISP (Internet Service Providers) all over. Maybe you'll find one for you here: Free ISP links
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TCP/IP...?

On New Year's Day, 2003, the Internet celebrated a 20th birthday, so to speak. Though there are many
claims to the "birth" of the Internet, January 1, 1983 marked the Net's transition from Network
Control Protocol(NCP) to Transmission Control Protocol and Internet Protocol (TCP/IP). Some historians claim the Internet was born in 1961, when Dr. Leonard Kleinrock first published a paper
on packet-switching technology at MIT. Others cite 1969, when the Department of Defense commissioned the Advanced Research Projects Agency
Network, known as ARPANET, to research a communication and command network that could withstand a
nuclear attack. Some 1970s Internet milestones: the advent of e-mail and the splintering off of ARPANET from
military experiment to public resource. Another milestone is the acclaimed Jan. 1, 1983, switch from Network Control Protocol to
Transmission Control Protocol and Internet Protocol (TCP/IP). The transition from NCP to TCP/IP may not have been the sexiest moment in Internet history, but it
was a key transition that paved the way for today's Internet. Protocols are communication standards that allow computers to speak to one another over a network.
Just as English speakers of different dialects and accents can often understand one another, protocols
provide a lingua franca for all the different kinds of computers that hook into the Internet. Until that fateful moment 20 years ago, fewer than 1,000 computers that connected to ARPANET used the
primitive Network Control Protocol, which was useful for the small community despite some limitations. "NCP was sufficient to allow some Internetting to take place," said Kleinrock, now a computer science
professor at UCLA. "It was not an elegant solution, but it was a sufficient solution... a more general
approach was needed." Indeed, as ARPANET continued its exponential growth into the 1980s, the project's administrators realized
they would need a new protocol to accommodate the much larger and more complicated network they foresaw as
the Internet's future. Vint Cerf, credited with co-designing the TCP/IP protocol with Robert Kahn, said, "It was designed to be
future-proof and to run on any communication system." The switch was "tremendously important," according to Ronda Hauben, co-author of Netizens: On the History
and Impact of Usenet and the Internet.
"It was critical because there was an understanding that the
Internet would be made up of lots of different networks," Hauben said. "Somehow the Internet infrastructure
had to be managed in a way to accommodate a variety of entities." The decision to switch to TCP/IP was controversial. "A lot of people in the community -- even though we had
given them six months' to a year's notice -- they didn't really take it seriously," Kahn said. "We had to jam it down their throats," adds Cerf.

URL

URL Anatomy of a URL.
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