Without the / at the end as in http://www.example.com

Why?

Some directories do not use the trailing slash and the editors may have to edit it out. Why give them that irritation? But mainly, because that is the way that most drectories instruct you to do it. Other sites may want a different format and you should really do it the way each one wants.

The you are talking by a directory point of view. But I am more interested in a search engine point of view. What is better if you are focused on seo?

A search engine treats them as two separate url's so for seo you need to choose one or the other but not both when using it as a link back to your home page from internal pages on your site

like wise they are treated as separate urls by directories so if you submitted both of these url's to a directory you are in fact spamming which could or most likely would get both your urls removed

That means I need to submit sometimes http://www.example.com/ and sometimes http://www.example.com for google purpose, otherwise google will detect my backlinks as unnatural. Right?

Nope........

you use one or the other but not both

so you either use the slash or you don't use the slash but what ever way you choose then stick to it

"scratch my head" ... did I not explain it correctly on my first post ?

But if I always use the same link, will not google think I am adding backlinks myself?

you use the same url but vary the anchor text
url: http://www.example.com
anchor text: Blue Wigets

if a blog or directory will accept deep linking then you submit an internal page from your site but still vary the anchor text using text relating to this deep linking page
url: http://www.example.com/green-wigets.html
anchor text: Green Wigets

But if I always use the same link with different anchor text, will not google think it is strange behaviour that the link is always the same?
If the backlinks are natural someone will link to me as example.com/ and someone else example.com (always with different anchor text).

you asked the original question relating to you submitting your site to a blog or directory, so if you have submitted it correctly how can it vary ?

what search engines look for is patterns with automated submissions with the same url and the same anchor text, or site wide links with the same url and anchor text.

so if your submitting your site manually then this will not leave a pattern if your varying the anchor text but use the root url without the slash

http://www.example.com/

http://www.example.com

http://www.example.com/index.html

are all considered to be different url's, what i am trying to say is only use one and the one your best advised to use is http://www.example.com, without the slash

It seems to me that this discussion is conflating a bunch of things, some of which, I feel, confuse the original question.

A search engine treats them as two separate urls so for seo you need to choose one or the other but not both when using it as a link back to your home page from internal pages on your site

Slash and no slash in an inbound link to your root canonical url (generally your home page) shouldn't be an issue, because Apache mod_dir should add the trailing slash at the root. Both http://www.example.com (without the slash) will resolve to http://www.example.com/ (with the slash).

Try these two links and see that in both cases the home page is resolved by the url with the trailing slash....

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If your server isn't set up that way for the root, I'd either make adjustments or change hosts. The trailing slash setup for directories is usually done, btw, in a server config file, not as a 301 in .htaccess.

Generally... and again, this is only for a link to the default root domain... I usually use a slash at the end in the link code, because, as I understand it, this saves the server one step. Again, as I understand it, the performance difference is not significant if you leave this slash off. I'd submit whatever the directory seems to be using.

And, for the default canonical link, varying anchor text patterns for the search engines, slash or no slash in the visible anchor text should not be a concern. Worrying about this is splitting hairs. The engines are looking for unnaturally repeated keywords in the anchor text.

http://www.example.com/index.html , though, is a different creature entirely, and we'll get to that if I don't run out of steam.

More on trailing slashes before that...

Trailing slashes definitely can make a difference in urls when it comes to pages other than the top root, and how they resolve will depend on server setup. While that's beyond the original question, in light of the discussion here it should be mentioned....

Whether or not you use the trailing slash in your link depends on how the site is set up. It generally matters the most on sites with extensionless filenames, or on sites with pseudo-directories, where you can't rely on the engines to sort out the trailing slash and the lack of trailing slash... those are two different urls... and you need to do a rewrite.

The best discussion on WebmasterWorld that I've seen on trailing slashes is in the Supporters Forum, accessible if you're a subscriber...

WordPress SEO Basics
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The best single post on the topic I've seen is Jim Morgan's post in this discussion, the New to Web Development forum....

Trailing slash
Do search engines care?
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The question of index.html is also a long discussion. I'd look at g1smd's post, which I'm referencing in my link, in this discussion....

Home Page Still Not Coming Up in Google - has anyone fixed this?
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