How to make my font bold using css?

I'm very new to HTML and CSS and I was just wondering how I could make my font bold using CSS.

I have a plain HTML page that imports a CSS file, and I can change the font in the CSS. But I don't know how to make the font bold, can anyone help me?

You can use the CSS declaration font-weight: bold;.

I would advise you to read the CSS beginner guide at http://htmldog.com/guides/cssbeginner/ .

You can use the strong element in html, which is great semantically (also good for screen readers etc.), which typically renders as bold text:

See here, some <strong>emphasized text</strong>.

Or you can use the font-weight css property to style any element's text as bold:

span { font-weight: bold; }

<p>This is a paragraph of <span>bold text</span>.</p>

You'd use font-weight: bold.

Do you want to make the entire document bold? Or just parts of it?