HTML5 has some useful semantic tags for use. They're not actually necessary, but the point of 'Semantic Web' can be helpful for organizing a lot of content.
I just came across a simple <small> tag which I never saw before. It works as it sounds, the text gets smaller.
What if the !DOCTYPE html was not for HTML5 but other legacy doctypes, what are good alternatives besides simply doing following style/CSS adjustments?
CSS: p {font-size: smaller}
HTML attribute: <p style="font-size: ##%">This text.</p>