Transcript How does it work? What is the Internet? Computer Protocols • • • • • • TCP/IP: Transmission Control Protocol/Internet Protocol HTTP: Hypertext Transfer Protocol FTP: File Transfer Protocol NNTP:

How does it work?
What is the Internet?
Computer Protocols
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TCP/IP: Transmission Control Protocol/Internet Protocol
HTTP: Hypertext Transfer Protocol
FTP: File Transfer Protocol
NNTP: Network News Transfer Protocol
SMTP: Simple Mail Transport Protocol
POP: Post Office Protocol
Clients and Servers
Browsers -- Netscape
Internet Explorer (IE)
Resolution of the Monitor
Color Palate
Other Distortions
No Images Displayed
Why not load images?
Speed
• Pages must react in 0.1 second for the to feel that the system
is reacting instantaneously to his or her requests.
• Pages that react in about 1.0 second will allow the user's flow
of thought to stay uninterrupted, even though he or she will
notice the delay. The user does lose the feeling of operating
directly on the data.
• Pages that react in more than 10 seconds will loose the
user’s attention, especially without feedback. Feedback during
the delay is especially important if the response time is likely to
be highly variable, since users will then not know what to
expect.
How much material?
What works?
Content is KING.
•Content online should be updated as often as
the information changes.
•Give the user a reason to come back to your
pages -- change the information available!
Speed is the PRINCE!
•Keep pages small (fast to load and read)
•Use graphics limited
•Use multimedia only when it will improve
user’s understanding of the page.
Format
• The first page should always be limited to what the
user can see on one screen.
• Limit pages that require scrolling to the second or
later page.
• Do not require users to “click through” too many
pages to get to the option they want.
More Format Hints
•Make sure your pages will be attractive with
variations in the browser and size.
•Keep your format consistent between your
pages.
•Document your pages!
Documentation
• Location of your web page
• Date the page was last updated
• Name and/or email address to
contact in case of questions or
problems
• Name of your business
• Location or mailing address
• Telephone and/or FAX numbers
Help your customers find you!
• Provide a useful URL