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In order to make this web site (and ownership of a Personal Computer) easier
to understand, we've created this PC Primer page to explain many of the subjects
& terms you
may encounter. As you read the other pages of this web site, technical terms
that are included in this PC Primer will be linked to the location in the
PC Primer where the term is discussed. In addition, if you move your mouse over a
technical term (perform a mouse-over), you should see a 'screen tip'. This is a
little text box that appears on the screen near your mouse pointer. It will
contain a short explanation of the term.
A couple of disclaimers:
- This is a work in progress. It will be updated as often as
possible.
If there is a term that you feel needs to be explained or explained better, use the
PC Primer feedback
form at the bottom of the page to bring it to our attention.
- This PC Primer isn't intended to be an ultimate source of
knowledge. It is intended to provide the layman with, what we hope, is a clear
explanation of various technical terms that may not always be understood. We're trying
to dispense general knowledge while trying not to delve too deeply into the
technicalities. Please let us know whether or not we've succeeded.
INTERNET or WORLD WIDE WEB. There
are many parts to this discussion, and it can easily get pretty technical. With that in mind, we intend to only hit the more commonly
used options when many (often obscure) options are available. First, we'll take
a look at the internet as a whole. That discussion should flow into a discussion
of domains & web sites. Then, a few words about email followed by a few
miscellaneous topics & highlights.
- The Internet or World Wide Web is the largest public network in
the world. It's growing so quickly that a meter showing the number of new
web pages being published, worldwide, on a real-time basis would spin so
fast you wouldn't be able to read the one's dial and would have trouble with
the ten's dial.
- The Internet consists mostly of powerful computers called Web Servers and
the vast web of communications media that interconnects them all. All of the
data people access as part of their internet experience such as web sites, email, file downloads, databases, etc, etc, is
stored, using hard disk drives or optical disks such as CDs or DVDs, on web servers.
- When you click a link or select a favorite to 'go to' a particular
web page, what you're really doing is sending a request to the server
that houses (Hosts) that web site to please send a copy of each of the
files used for that particular web page to your PC so that it can be viewed
in your browser program (such as Internet Explorer®).
- In fact, the request doesn't even go directly from your PC to the
web site server. It travels through intermediaries. Visualize your
request as a package sent cross-country via UPS®.
- You ship your package.
{You select one of your favorite web sites.}
- When you hand the package to the
driver, it's scanned. This initiates delivery accountability.
{The
server, at your Internet Service Provider (ISP), that acts as your
Gateway to the Internet, accepts your request, time-stamps it and
sends it to the server that hosts the web site.}
- Your package travels towards its
destination. It's being tracked all the time.
{All along the way,
each server that receives & forwards your request tracks it until it
reaches its destination.}
[However, unlike UPS®, there's no
guaranteed delivery. If the destination server is turned off, for
example, delivery will be attempted. Once. If delivery fails, an
error is returned to your PC telling you that the web page you
requested was not available. Congestion on the Internet can also
cause this problem. Try going to a totally different web site. If the new
web site loads in your browser, the trouble is likely with the
original site's hosting server. Wait a few minutes and try the
favorite again.]
- Your package ultimately
arrives at it's destination. {Your request is received, decoded and
acted upon. The server immediately prepares a number of packages to
be shipped back to you (at the speed of light - less network
congestion). These packages contain all of the images, words, ads, etc
that make up the web page you just requested. They are all tracked
just like your package was.}
- The gateway server at your
ISP (the the hypothetical UPS® driver)
receives all of the packages and delivers them to your PC as soon as
they're received and in the order they're received.
- As soon as the packages are
received by your PC, they're unwrapped and delivered to the browser program.
The browser then takes all of the web-site pieces from the packages
and reproduces the web site on your screen.
- Of course, all of this should take place
in much less time than it takes for our explanation.
- Domains, Web Sites & Web Pages. Right now, you're reading a web page
that's part of a web site published to a domain which is hosted on a server.
This is how it works:
- If you look near the top of this window, you should see an Address Bar.
In it, depending on how you arrived at this page, there might be an address
that reads:
http://www.onenoteenterprises.com/PC_Primer.htm
This means that you are viewing the file called "PC_Primer.htm" using the
"Hyper-text Transfer Protocol" (http). This file is located at the domain "onenoteenterprises.com"
which is on the World Wide Web. You are also viewing the files that are
associated with "PC_Primer.htm" such as our logo (a .gif image), the
navigational buttons used to move from web page to web page and even the
horizontal lines we use to separate topics. Each of these files is
transferred to your PC and stored in the folder called "Temporary Internet
Files" located in your computer's "Windows" folder.
NOTE: You can look at these files using Windows
Explorer, but don't try to delete them that way. If you're using Internet
Explorer as your browser, follow these steps:
- Click the big, blue 'E' icon on your Desktop with
your Right mouse button.
- A menu will appear on your screen. Click the menu
item called 'Properties' with your Left mouse button.
- Alternatively, while the browser is open, click
the Tools menu and select Internet Options from the menu.
- A Window will appear on your screen called
"Internet Options". You will immediately see the three sections on the
'General' tab:
- Home Page. This is where you change your home page
(the page that opens when you start your web browser). [Hint: Most people
DON'T use the Blank Page option and we can't think of any reason to
recommend it.]
- Temporary Internet Files. We'll get back here in
just a minute.
- History. This is where you purge your web
browser's history. Click the 'Clear History' button if you would prefer that
others not be able to see which web pages you've recently visited.
- Getting back to Temporary Internet Files: From
this screen, you can delete all of the cookies or all of the temporary
internet files you've accumulated while surfing the web. Just click the
appropriate button. (Most users have no need to change any of the settings.
So, after you look at them, click Cancel to return to the Internet Options
window.) When you delete your Temporary Internet Files, if it takes a long
time (more than about thirty-seconds) for all of the files to delete, it
means that you need to delete these files more often.
- If you want to delete all of the temporary
internet files each time you close your internet session, click the
'Advanced' tab (across the top of Internet Options). Scroll down to the
security settings, and click a check-mark next to, "Empty Temporary Internet
Files folder when browser is closed" then click the 'Apply' button at the
bottom of the window.
- When you're finished with Internet Options, click
the OK button.
Domains and Domain Names. A Domain or Domain
Name is an address on the World Wide Web. Its home is a specified amount of
storage space on one of the hard drives connected to a server which, in
turn, is connected to the Internet. Files are placed in this space, usually
for viewing (such as a web site) or downloading.
Buying (leasing) your domain. The rights to
domain names are leased for $40.00 for the first two-years. (Promotions by
some web hosting companies can reduce this cost.) A domain name can be
renewed for as long as it's wanted after the initial two years. Prices for
renewal vary. Also, since a domain is a registered name, it is property and
the rights to it
can be bought & sold.
Hosting your domain. Domains require hosting
in order to perform their function of being the web address for a web site.
While hosting your own domain is legal, it's expensive and can be
technically challenging for the non-professional. Most domain owners use a
hosting service. Many different types of web service companies provide
hosting services. Domain or Web Hosting companies and Internet Service
Providers (ISPs) provide the bulk of available hosting services. Prices and
quality of service will vary, so shop around.
Choosing your domain name. Most companies
that provide hosting services also provide domain name lookup services.
Since domain names are leased on a first-come-first-served basis, the
prospective buyer of a new domain name may have to try many possibilities
before finding an available domain name that's also desirable.
- Email. Email has become the written
communication medium of the new millennium. Anyone who can access a PC
that's connected to the internet has access to email. Email addresses are
available from your ISP with your dial-up or broadband internet connection,
they're available (usually free) from various internet-based companies (such
as Yahoo®) and they're usually packaged as part of domain hosting
accounts.
- How email works. email can be PC-based using a program such as
Outlook Express, web-based like Yahoo Mail or be provider-based such as AOL.
In all three cases, the email, itself, works the same. The difference is in
the method used for accessing & using the email. We'll discuss these
differences in the section called 'Accessing your email'.
First, let's break down the basic email address. We'll use
'johndoe@xyz.com' as our sample email
address. Just as our postal address has our name & street address, our email
address has a 'name' (johndoe) and a delivery address (xyz.com). The '@' is
the designated separator that identifies the whole thing as an email
address. The 'name' in the case of an email address is usually referred to
as a User ID or Account Name. The delivery address is a domain name.
- Generally speaking, when an email is sent it initially goes to a
specially programmed computer called an SMTP (or outgoing email) server. All
this server does is to receive the outgoing email from you, process it and
send a copy for each user ID to the matching domain found in each email
address listed in the address section of the email. Depending on the size of
the email, each copy will be broken into smaller pieces for the transmission
to the receiving domain (then reconstructed upon arrival). However, it does
this little thing for every email sent for processing & transmission by each
user connected to the server. Most outgoing email servers handle a million
or more emails each day. If the domain section of an email address isn't
valid, the server sends an error email to the sender of the original email
announcing this error and that no further processing will take place.
- Once the email arrives at the receiving domain, it is directed to a
server that's dedicated to handling received emails. This server is usually
referred to as a POP server (in the case of AOL, it's called an IMAP
server). Regardless of the server type, the same general processes take
place.
- All of the pieces of the email are received and it's reconstructed.
- The account name is verified as being valid & the email is placed in the
'Mailbox' associated with the account name. If the account name isn't valid,
one of two things will happen: 1) The errant email will be delivered to a
human administrator (the domain's Postmaster) for action, or 2) An error
message email will be created by the server program, and sent to the person
who originally sent the email, announcing that the destination address is
invalid.
- When the user who has the email account requests email from the mailbox,
the emails stored in the mailbox are sent to that user's PC. After all the
pieces have been received & reconstructed by the email program on the user's
PC, well, as they say, "You've got mail!"
- Accessing your email. There are many programs available for the
purpose of providing access to email. Windows comes with Outlook Express, MS
Office comes with Outlook, AOL & Netscape have their own email programs
built into their interfaces and there are also third-party applications such
as Eureka. Finally, there is web access (using your web browser to handle
your email) which is available with such portals as Yahoo or Excite as well
as some third-party mail access web pages. While all of these email programs
does the same job, each does it in a slightly different manner. One of the
notable differences is where your emails are stored. AOL and web-based email
store your emails on their mail servers. Eureka & the Outlook programs store
your email on your PC.
We don't intend to provide operating instructions for all of
these programs. What we will provide is explanations of some of the various
terms associated with email handling.
Addressing your outgoing email. Addresses can be attached to an
outgoing email in the To:, CC: and BCC: sections. While To: & CC: (carbon
copy) are pretty self-explanatory, the BCC: section isn't so clear. An email
with an address in the BCC: (blind carbon copy) section will be delivered to
that address without any of the other recipients knowing that that address
was part of the the email.
Replying & forwarding emails. Sometimes it's desirable to respond to
or share an email with a friend or co-worker.
When you click either the 'Reply' or 'Reply to All' buttons a
whole new email is created. Depending upon your preferences, the original
email may or may not be quoted as part of your reply email. If you Reply,
only the originator's email address will show up in the address lines. You
can add other addresses as required. However, if you click the Reply to All
button, all of the addresses that received the original email will become
addresses of your reply email. Again, you can add or delete addresses as
required. If there's an attachment to the original email, it won't be
attached to either type of Reply.
Forwarding an email is a 'free-form' method of sharing the
contents of an email. No addresses are retained for delivery from the
original email. When you Forward an email with an attachment, the attachment
becomes part of the new email. Forwarding is the most flexible way to share
an email with someone else. You can even forward an email that you
previously sent to someone else if it's stored in your Sent Items folder.
Safely reading your email. One of the unhappy surprises we all find
in our emails are viruses, Trojan Horses or other malicious files. While
everyone should have an antivirus program screening received emails, there
are other things you can do to make your email safer to use.
Most email programs provide a 'labor-saving device' called,
in Outlook & Outlook Express, the 'Preview Pane'. The Preview Pane is
usually associated with the Inbox folder. It allows the user to click a
received email in the Inbox to see a preview of it (usually) below the list
of emails in the Inbox. This is a dangerous way to manipulate your email
since some malicious emails can do their damage as soon as they're previewed
(opened). It's much safer to be able to select specific emails to view (or
otherwise check out) retaining more control at the user level.
Which emails should you open? First: Known spam should never
be opened without being pre-screened. This goes double for spam containing
attachments. Be very careful with these emails because the attachment is
usually a malicious file of some sort. Second: Any email with an attachment,
even if it's from a known correspondent, should be considered suspect. If
you're not sure, check with the originator of the email to ensure that it's
legitimate before you open the email.
What can you do to protect yourself? One of the best options
is to set your email application's preferences for received messages to read
them in text format (rather than RTF, Word, web or HTML which are 'Active'
formats). Text format doesn't allow malicious code or attachments to infect
your PC. Another option, if you've chosen to use HTML (or another active
format) as your viewing format, is to pre-screen suspect emails by looking
at their 'Source Code'. Looking at the source code allows you to look at the
contents of the email in text format prior to opening the email in one of
the active formats. This method requires a bit of experience in order to
interpret what you're seeing, but can be very effective. Finally, newer
versions of Outlook & Outlook Express have an option to block all
potentially dangerous attachments from being saved or opened. This option is
effective until it blocks that picture of the new grandchild or some other
expected attachment. At that point, it gets turned off because it's too
inconvenient.
Bottom line: The best protection is to be careful and
maintain an up-to-date antivirus program that screens for email viruses.
MODEM. MODEM stands for MOdulator/DEModulator. It's a device that allows two
computers to connect to each other using either Cellular or Landline (AKA: 'Plain Old
Telephone Service' or POTS) telephone service. They're commonly used today to connect to the
Internet at speeds that are less than 56.6 kbps and are referred to as Dial-Up connections.
Popular usage has extended the use of the term MODEM as the name of the device
used for Broadband Internet connections (this device is actually a type of
Network 'Switch' which is a combination Signal and Protocol converter).
NETWORK. Any group of computers or devices that are connected. It can be as small as two
PCs that share an internet connection (a Local Area Network or LAN) or thousands
of PCs in a global, corporate system (a Wide Area Network or WAN). Networks can
be wired (usually Ethernet) or wireless or both. Some common terms associated with
Networks are:
Network Interface Card or NIC. A device that is attached to each
PC in a network. This is the interface that allows each PC to
communicate with the other parts of the Network. It can be installed
internally (as a PCI or PCMCIA card) or externally (using USB, FireWire or
Bluetooth). Each NIC has a unique identifier that
allows the device controlling the local network to identify each PC on the
network. A NIC used on a wired network will have one or more plug receptacles depending on the
type of wire cable it uses to connect to the rest of the Network. Most local
Networks today use CAT-5 Ethernet cable. A wireless adapter could also be
considered a cousin to the NIC.
Protocol. This is the 'language' all of the devices on a network
use to 'talk' to each other. It includes the means of identifying each
device on the Network & which device (if any) is controlling the network.
It also dictates
how information being moved between devices is packaged for transmission,
transmitted, received, unpackaged & reassembled as an identical copy of the
original information. The NIC on each PC handles
these tasks for that PC.
Routers, Switches, Access Points & Hubs.
"Lions, tigers and bears.
Oh my!" These are the dreaded 'Network Devices' that only techies seem to
understand. Each one has a particular purpose:
- The Router is the 'heart' of the Network. It uses the NICs to
identify each PC (or other device with a NIC) and then assigns each device
a unique Network Identifier (such as an IP address, i.e. 192.168.1.101).
It then controls Network communications using the Protocol it's
programmed to use.
- Access Points are the Routers of the Wireless (or
combined wired & wireless) Network.
- Since different types of Networks use different types of electrical
signals and different protocols when they communicate, in order to
connect different types of Networks to each other a device is needed to
convert one type of network's electrical signal containing information
using a particular protocol to the electrical signal and protocol that
the other network uses. This device is a Switch. Everyone with a
Broadband Internet connection has a switch. You might call it your
'Cable MODEM' or 'DSL MODEM', but it's still a switch.
There are other switches that have the same input & output. These are
used as signal amplifiers (or powered hubs) in networks that have groups
of devices that are physically separated from the router by more than
about 150 to 200 feet.
- Finally, we come to the Hub. Routers and switches have a limited
number of cable receptacles (or ports) for connecting to the other
devices on the network. A hub can be connected to one of the router or
switch ports to allow multiple devices to connect to the network on one
port. Usually a hub is added to an office network to provide network
connectivity to a group of workers in a common location. Think of it as
an extension cord for your network - you plug it into one receptacle and
ten feet away you have three receptacles to use. It's also the same principle
as the USB Hub many PC users now have on their desks.
PERIPHERAL. Peripherals are devices that attach to a PC or PC network. They
are then operated by one or more PCs. Some common examples are: Printers, Sound
Cards & Speakers, MODEMs, Disk Drives, Network Interface Cards (NICs) and PDA
Cradles. Depending on purpose & design, they may be external or installed inside
the PC case.
PC Primer Feedback
If you would like to help us improve our PC Primer, please send an email
to
support@onenoteenterprises.com. We will also provide your with feedback
on your request if desired.
[We don't share any information (email addresses,
etc.) about anyone with anyone else unless that
sharing has been agreed upon in a client/consultant environment.]
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