When you're first learning HTMLheck, even after you've been doing it for a whilethere are some easy-to-make mistakes.
Common Problem #1: Missing Delimiter
Ooops! That tag just isn't working. The first thing to check is: does it have both the opening (<) and closing (>) delimiter. It's easy to accidentally forget or delete one as you edit your page.
Common Problem #2: Missing Quotation Mark
Are things just disappearing from you page? Check to be sure that every place you've used an open quote in a tag, there is also a closing quote. If a browser doesn't find a close quote, it will think everything on the page is part of the tag attribute value rather than content to be displayed.
Common Problem #3: Missing End Tag
Suddenly you have some odd indents. Or all the text is bold. You probably entered an opening tag, but forgot to enter the ending tag.
Common Problem #4: Good Old Typos
The tag isn't working as you expected. Go back to your file and double check for old fashioned typos. It's almost embarrassing how often a <br> tag-typing finger can slip a little and create a <bf> tag instead. The browser just ignores that alien <bf> tag because it doesn't understand it.