Readability - CD/web site?

[Geoff Hart]

Julie Nelson wondered: <<My team is developing a marketing CD for our 
retail computer system. We're in the initial stages of developing the 
layout for the main navigation/home page.  So far, we've developed 2 
different layouts.  One has a white background, black text, navigation 
buttons with a red border at the top, a few images & the very top of 
the page has the company & computer system logos with a  black 
background behind it.  The other layout has a black background, white 
text, the same company & computer system logos with a black background 
& a few images.  It might just be my eyesight, but it's more 
challenging for me to read the white text on a black background than 
black text on a white background (or maybe this is just what my eyes 
are used to).>>

My experience is the same as yours: black text on a white background 
works better. Indeed, reversed type is sufficiently uncommon in 
materials designed to be read (as opposed to "designed to be pretty") 
that unfamiliarity alone makes reversed type a poor choice. However, 
note that "unfamiliarity" is the key word: in the bad old pre-Mac days 
of using dumb computer terminals, I found white on black much easier 
than the alternatives (amber and green text) and had no complaints 
about its efficiency.

One powerful argument against white text on a black background or any 
other form of reversed type in large quantities: Anyone who has to 
print out the information will hate you with a fiery passion. Several 
pages of black background will drain your inkjet and poison you with 
ink fumes, or will clog your laser printer with dropped toner. Yes, 
there are ways around this, but most users won't know them. (I say that 
based on anecdotal evidence from a great many years spent sorting 
through the output tray on a departmental laser printer trying to find 
my own printout.)

<<Do you know of any readability studies available on the web that 
reference what background color/font color/font size & type is easiest 
to read on a CD or web site.>>

Nothing I can put my hands on without a fair bit of digging, but a 
Google using appropriate keywords (legibility, contrast, text color, 
reversed type, etc.) should turn up a range of information. Of course, 
you need to filter that information; peer-reviewed articles in journals 
are more reliable than speaker notes, and university Web sites are more 
reliable than Usent postings.

My gestalt for what I have read is that (as noted above) familiarity is 
the biggest issue so long as you preserve strong contrast between the 
type and its background and choose an appropriate font (serif and sans 
both work fine at an appropriate text size). Perhaps more importantly, 
readers vary in their abilities and preferences.

My take on typographic design for the screen is that onscreen text 
should be adjustable by the reader so they can choose their own font, 
size, and foreground and background colors. Why not build this utility 
into your software? It should be trivial to offer the reader a choice 
of several CSS styles if you're using HTML, or several different 
versions of the same file if you're using fixed-format material such as 
PDF.

<<I'm guessing I could find something on Jakob Nielsen's site.>>

Wouldn't surprise me, but you'd be ill-advised to accept his 
pronouncements uncritically. There's gold to be found there, but also 
much pyrite and glitter paint.

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Geoff Hart   ghart at videotron.ca
(try geoffhart at mac.com if you don't get a reply)
www.geoff-hart.com
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