Don't fret over < strong> & < b> tags with regards SEO Craig Murray DigitalMatt Cutts reassured us today in his latest video that there are indeed no differences between using <strong> or <b> tags when it comes to SEO and its best practices. 

The full question that was asked:

In terms of SEO, what is the difference between <strong> tag and <b> tag for emphasis on certain words of text. From the user perspective, both tags have the same effect (words in bold). Which tags should we use in which circumstances?

Cutts mentions that there is no difference when it comes to these tags when it came to ranking, scoring or other search factors. He added the same is true for or the <em> and <i> tags when using italics.

Cutts explains the <strong> tag is technically talking about presentation. The <b> tag is a semantic label, but, he says, “In practice, every browser just goes ahead and makes it bold.”