<WBR>

<WBR> is for the situation where you have used <NOBR> to prevent line breaks in a section of text, and then you want to say "but you can break HERE if you want". <WBR> does not force a line break, it merely allows one:

<NOBR>Maybe it's because every time I get to the last line I feel like I have 
so much left to say that I have to try to <WBR> push and fit and cram as many 
words I can think of as I possibly can</NOBR>

produces

Maybe it's because every time I get to the last line I feel like I have so much left to say that I have to try to push and fit and cram as many words I can think of as I possibly can

Having invented <WBR>, Netscape now seems to have abandoned it. It's better to stick to grouping non-breakable sets of words within <NOBR>, like this:

<NOBR>Maybe it's because every time I get to the last line I feel like I have 
so much left to say that I have to try to</NOBR> <NOBR>push and fit and cram 
as many words I can think of as I possibly can</NOBR>

which gives us this paragraph:

Maybe it's because every time I get to the last line I feel like I have so much left to say that I have to try to push and fit and cram as many words I can think of as I possibly can