Beauregard said:
Justified text always has varied spacing between words.
Usually, but not necessarily. Sometimes spacing does not vary, since all
text fits without extra spacing, by accident. Moreover, it is possible to
justify by increasing letter spacing, though this is usually coupled with
some variation of word spacing as well. Web browsers generally use just a
coarse method that divide the extra spacing needed evenly between word
spaces. (You might get something better using nonstandard CSS features.)
Regarding David's question, the particular page
http://films.profectus.com.au/
appears on my Firefox so that in the left column I see
"The search box below will
locate any information
about the films that is
recorded on any
referenced web page."
Since amount of text on a line varies a lot, justification causes rather bad
spacing especially on the line "recorded on any" - the spacing between the
words is larger than the short words!
This happens on a fairly wide browser window, which happens to consume more
half of the screen width of 1680 pixels. (I had probably last used Firefox
on a page that needed a wide window.) In a narrower window, things often get
much worse. The point is that division into lines depends on the available
width. Actually, it would make much sense to set a reasonable minimum width
for a text column. But it would not really solve the problems caused by text
justification.
Every
time my fast-reading eye encounters a longer than usual space, it
pauses.
Justification reduces readability somewhat. In this context, it's perhaps
more important that it often causes a visually unpleasant effect when the
line length is small and when no hyphenation is applied. In books,
justification is common, but it is coupled by advanced typesetting software
and automatic hyphenation (often with human checking and correction, at
least in quality books). Web pages are something completely different.
In special occasions, you can manually (or programmatically) hyphenate a
piece of text, using ­ (soft hyphen). This might work for short pieces
of texts that you wish to justify. For copy text, it's just too awkward.