Underline links?

[Daz]

I don't usually underline my links when designing sites except for on hover, I just think a load of underlines on a page makes it look cluttered. However, from an accessibility point of view, should I be underlining them always?

[redux]

yes you should. otherwise, how do you identify what's a link and what isn't ? just using colour won't work (colour blindness may prevent users from seeing them). same with bolding. you may run into problems with user with cognitive disabilities as well.
these rules would, in my opinion, apply mostly to links inside the normal flow of text. if you have a side navigation, it may be argued that it's clear those are links...but it really depends on the situation, and non-underlined links should be the exception. my view on the subject, anyway

[Zopester]

If you really don't like the solid underline of "text-decoration:underline", you could always try "border-botton:1px dashed #000". Gives a nice effect (in certain situations) and remains obvious to the user that they are looking at something other than ordinary text.

Having said that, I usually use this very effect for abbreviations/acronyms. So maybe I'll shut up and go have another coffee.

[Daz]

Yeah same here with the dashed underline. I guess it's time to break an old bad habit then!

[anode]

I think the dashed thing is becoming a convention for abbreviations. I considered using it to denote off-site links, but I think it creates too much confusion.

Redux:Out of curiosity, how does bold confuse those with cognitive disabilities but underline doesn't? Has this been tested or is it speculation+Nielsen?

[redux]

Redux:Out of curiosity, how does bold confuse those with cognitive disabilities but underline doesn't? Has this been tested or is it speculation+Nielsen?

first of all...what's with the confrontational tone ? and who said that i believe what nielsen says ?

anyway, you may see from my post that i didn't say "bold will confuse people with cognitive disabilities". it was a standalone statement, and what i meant was: bold should not be used to denote links if there are other elements on the site's text which are bold, but are not links. otherwise it gets confusing (is that text bold because it's a link, or bold because it's emphasised, or maybe it's a small title...)
to reverse the argument, underlines should not be used for anything other than links.

now, as for how this relates to cognitive disabilities, please cast your eyes on the WAI WCAG guideline 13 http://www.w3.org/TR/WCAG10/#gl-facilitate-navigation

Clear and consistent navigation mechanisms are important to people with cognitive disabilities or blindness, and benefit all users.

so, clear and consistent. which means: if you use anything like bold for links, then all text in bold should be a link. but it should also be stressed that we should keep to commonly used conventions to ensure that users will be able to use our site without having to re-learn how to use websites in general. underlines have been the de-facto identifier for links. anything else will require the user to change his/her ways (and this can be more difficult for users with cognitive disabilities).

[anode]

No confrontotional tone from me(at least not intended), but I sense a bit from you. I'm sure we can bury the hatchet. I brought up Nielsen because of his complicity in the "links should be underlined" nonsense which is a pet peeve of mine. I didn't notice the second was a separate statement, as the first was a sentence fragment.

FWIW, my informal testing(asking a bunch of non-techies including some people one may consider to have "cognitive disabilities"{my highly dyslexic best friend, and a 10 year old with moderate learning disability}) indicates that bold is on par with underline at this point as far as being a convention. I asked around 12 people how they know a piece of text on a page is something they can click on. The answers were usually in this order:

• It's a different color.
• Something happens when the mouse is on it(when prompted usual answer is color change and cursor changing to a hand.)
• It looks different(when prompted, all said something to the extent of "It's bold or underlined", not necessarily in that order.)

Since this was brought up, I checked Dive Into Accessibility.

The second potential problem is the link decoration. If your CSS redefines a rule to make your links a different color, you need to make sure that the links are also distinguishable in some other way, like bold, italic, or underline. Otherwise, the link text might be perfectly readable, but colorblind people won't be able to tell that it's a link. This is illustrated below.

emphasis mine

[redux]

No confrontotional tone from me(at least not intended), but I sense a bit from you. I'm sure we can bury the hatchet.

anode, i apologise. i was in a cr*ppy mood this morning because of hassle at work, and completely misinterpreted your post's tone.
no hard feelings i hope...

[Webnauts]

Links and Usability:

Some links are missed by users because the links are not evident. Links must be clearly designated so that there is little (or no) uncertainty on the part of the users as they click on a link. Research has shown that when users were given visual cues to locate links, as opposed to using the pointer to search for links, they were able to find the information seven times faster.

[Webnauts]

Interesting further reading:

http://psychology.wichita.edu/mbernard/abstract.htm

[Webnauts]

Another interesting link:

http://www.humanfactors.com/downloads/oct00.asp

Though I do not agree with all points mentioned there. Just Dr. Baileys point of view.