I've been meaning to write about this for ages. I've been putting it off because I wanted to provide thorough and well-researched guidelines on best practices for choosing link text, but that's not gonna happen anytime soon, so I'll start with a less-thorough version.
By "link text" I mean the text of a link—the text that appears, marked as a link, on a web page, and you click it and the browser takes you to another page. In most traditional visual browsers, if the page author hasn't done something to change link appearance, the link text appears in color and underlined to indicate that it's a link; and when you point to it with the mouse pointer, the status bar of the browser indicates the URL that you'll go to if you click it.
In the below discussion, the links are mostly null links; they're just there so that you can see what the link text is.
There are a couple of longstanding traditional approaches to choosing link text that, although very widespread, have unfortunate side effects. These include:
- Phrases like "For more information, click here."
- Attaching a series of links to a series of words.
- Writing out the URL and attaching the link to it: http://www.kith.org/.
- Less common: using an entire paragraph-long quotation as link text.
What's wrong with those approaches? you may ask. Here are a couple of the main problems with them:
- They're bad for people with disabilities, especially visual disabilities, especially blind people. Such people often use software called a "screen reader" to read the text of web pages aloud to them. A screen reader reads the link text aloud for each link as the user steps through the links to decide what to click. If you're having a hard time imagining this, try closing your eyes and have a friend read you the link text (and only the link text—not the surrounding plain text) for each of the above examples. Can you tell whether you want to follow the links? Now imagine you're on a page where there are ten links, and they all have the text "here." Can you guess which "here" is the one you want? The third example above is a little different; for that one, have your friend read each letter and punctuation mark of the URL aloud to you, slowly. . . . If you want more information about web accessibility, I recommend Mark Pilgrim's excellent Dive Into Accessibility.
- As is widely known (I'm not giving away anything secret here), Google uses link text as part of its ranking algorithm; hence the practice of Googlebombing. If all of the links to a given page use the word "here" or "a" or the page's URL, then that page isn't as easy to find in Google as it could be. If I've got a great page on wombats, but everyone who links to it says "click here for wombats" or "http://www.example.com/Jed-wom-page.html," or links to a series of my subpages with "these are cool pages," then Google isn't going to know that you think my pages are good search results for the search term wombat.
So if possible, you should avoid those kinds of bad link text. (I know that some people don't understand the fundamental fact of the web, that you can click links to follow them; I know if you don't say "click here" some people won't know they can click to follow the link. I'm afraid my answer to that is that that's too bad, but that those people are going to miss out on most of the web until someone teaches them that they can click words other than "here.")
If you want to write really good link text, you can go a step further: make your link text give a clear indication of what it is you're linking to. This is where I keep bogging down; I haven't yet come up with a good firm set of link text style guidelines, nor have I seen such a thing online (though I'm sure it must exist). I generally try to link from a noun or a verb, to link from a phrase that describes the destination, and so on, but I haven't worked out details. Is it better to link from an article title or a description of the article? I'm not sure; I generally play it by ear, often based on how descriptive the title is. But it's definitely better to use an article's title as link text (in most cases) than to use just the name of the publication; if you've written the phrase "a New York Times article on wombats," far better to link from article on wombats (or possibly the whole phrase) than to link from just New York Times.
Sometimes writing good link text requires reworking a sentence. It often feels natural to say "For more information, click here" or "For more information, follow the link." But when you find yourself writing such phrases, take a look at the link text and imagine it in isolation, and see if you can come up with a rephrasing that has better link text. In some cases, you might try the simple change "For more information, see Wombats R Us," but sometimes that doesn't fit with the context. "For more information, see the article" isn't great, but it's better than "click here." But sometimes you may need to rework the entire sentence, and sometimes the results are a little clunky. I sometimes find myself writing things like "A New York Times article on wombats has more information"; sometimes you'll have to decide whether it's more important to you to go with good writing or good link text.
But at least you should make that an informed decision. And often, you can satisfy both goals at once with very little rewriting.