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The following guidelines will help Web developers to cater for the needs
of all Internet
users.
Screen layout should be consistent. The more consistent a
Web site is in its design the easier it will be for users to navigate. Users,
particularly
older users, tend to learn and remember the location of key functions and controls.
Screen layout should include logos, navigation buttons and footer
information. Putting the logo in a consistent place on every page, usually
top left, ensures that visitors are
fully aware
that they are on the same site.
'Page Last Updated' information is also useful
- visitors will quickly know if you have added any new content to your site,
and it may prompt you to do so. The date format should be understandable
- 1st February 2003 is better that 02-01-03. In the UK 02-01-03 means 2nd January
2003.
A link to the home page should be added to every page except the homepage
itself. Pages should not link to themselves as this can confuse some users.
Making your logo the home page link is considered to be good practice.
36% of Internet
users still use modems with connection speeds of 33K or less. Pages should
therefore be kept to a maximum of 35K ensuring
download times of less than ten seconds for these users. Visitors may not wait
if your pages take too long to download.
All images, including spacer images, should include alternative text. The
alt text should describe the function of the image if applicable. You should
use alt="" for spacer images and other 'eye candy'.
Frames should not be used unless absolutely necessary.
Frame-based sites can be confusing for the visually disabled, particularly
those using screen readers or speech browsers - users can easily become disorientated.
Additionally, users cannot easily bookmark individual pages within a frame-based
site.
Each page should have a descriptive and different title, clear and helpful
headings, and a logical structure.
Titles are used by search engines to identify Web pages. If two or more
pages have the same title they cannot easily be differentiated by users.
The FONT tag should generally be avoided in creating accessible Web sites.
While attribute specifications like SIZE="+1" or SIZE="-1" are
relatively harmless, absolute sizes like SIZE=“1” can result in
text that is too small to read. Instead Cascading Style Sheets should be used
to format Web pages. Style sheets allow authors
to
suggest
relative
changes in font size with much greater flexibility than is allowed under FONT.
The COLOR attribute of the FONT tag should always be avoided since many
browsers still display the font colour when the user tries to override author-specified
colours.
The result could be an unreadable document if the font colour does not contrast
well against the reader's chosen background.
The FACE attribute of the FONT tag can not be overridden by the user
in many browsers. This may result in the author choosing a font that is very
difficult
to read given the user's platform and environment settings. The same font
may
display strangely on different platforms.
Text should be the equivalent of size 12pts to enhance reading
performance. Research
has
shown
that there is no noticeable difference in reading speed or user preference
between Times New Roman, Georgia or other serif fonts and Helvetica, Arial
or other sans-serif fonts.
Links should be clearly identified and make sense when read out of context.
Links should never be designated with the text 'click here'. Some
screen readers can be set to read out a list of links on a particular page;
a list of 'click here' links is not helpful.
Blue underlined text is
the preferred choice for all links. Some users miss links
because the
text
is not
underlined. Research
shows that users can easily find links
which include visual cues, that is, links that are underlined, rather than
having to
move the mouse to see when the pointer changes to a hand (this is known as
mine sweeping). Visited links should be designated
using a
different colour. Many users use link colours to identify which parts of
a site they have already visited.
Pages should be fluid/flexible
because users browse the Internet using a variety of screen
resolutions. Pages should be designed to expand or contract according to the
user’s settings,
thus preventing horizontal scrolling. Horizontal scrolling is a particular
problem for screen reader users because the screen reader does not automatically
scroll
horizontally – users may miss important content. An excellent flexible
pages tutorial has been written by James Shook.
Pages should be device independent.
Not all users navigate Web sites using a mouse - many disabled users use
Assistive Technology. All users should be able to navigate the site using
the input device of their
choice. Keyboard shortcuts, using the 'accesskey' attribute, should be provided
for key links.
Content should comply with Plain
English Guidelines. Text should be
left-justified, active verbs should be used rather than passive verbs and there
should be no flashing or
moving text.
Everyday English should be used instead of terminology and there should
be no background images or music. If you insist on having music on your site
you should give users the option to turn it off. Better still, give users
the option to turn it on if they wish.
Paragraphs and sentences should be kept short. Readability improves when sentences
and paragraphs are kept relatively short. Users tend to scan Web pages and
will often skip over large chunks of text.
Conclusion
I'm sure there are lots more excellent Web design and content guidelines.
If you send me your suggestions in an email I'll
add them to the next update of this page.
Supporting Links
Research-Based Web
Design & Usability Guidelines
Browser News
DreamInk Web Design |
