String or bold font uses

hey guys.....

please anyone tell me which is better to use for dark font. you have only two options. please help me i am in confused.

1. Bold <b>
or
2. Strong <strong>

bold tag is useful

as part of the factors will go for BOLD, but not a big deal actually.

Actually I use these things when I think that any title or any sentence which is more emphasize the hole content of the page or which one reflects summary of content which attracts for our visitor I use strong because I use dreamweaver and has an option just click on B and your selected content become bolt.
I don't any seo experience with these options.

This is an Accessibility vs Presentation issue.

<b> and <i> are presentational text formatting tags (and have actually been deprecated in XHTML2 I think) where <strong> and <em> have semantic emphasis for screen readers etc and browsers just happen to have chosen to display them as bolded and italicised text.

Given that you can style text anyway you want using CSS, this is almost a moot point, but if I had to choose I'd go for <strong> and <em> (and have been using them for years) since they have presentational benefits AND they're Accessible.

I think it makes more sense to use them from an SEO point of view too, for the same reasons since Google will understand the difference. They probably treat them the same, but if it could help, why not do it and we should all be doing it anyway because all websites should be Accessible.