If I see information which I feel is important, is it appropriate to make that text bold so it is noticeable?
Most of the time no; it is common to highlight important terms the first time they are met, but we don’t tend to highlight whole sentences unless they are really vital. Usually all of the text is important, otherwise it wouldn’t be there.
You can use the Note style for information that is unexpected or not obvious from the preceding text. The Note style is created by a block-level CSS class, so the text you apply it to should be a whole paragraph.
Our general rules are to use the
<strong> element the first time a new term is introduced, right before you explain what it means. When a word or short phrase needs to be emphasized within a sentence, you can use the
<em> element around it.
Otherwise, as @jswisher said, you can use the Note style for a short paragraph if it is of significant importance, but generally this should be limited to occasional use as it’s distracting.
In my opinion, it depends on the specific location. Sometimes you just need to use a different font. Which is what I choose more often if something needs to be highlighted. But as I wrote, this is my opinion.