He was using <b> instead of <div> because it was shorter. That's a 4 byte savings on each button. If you had a lot of buttons on a page...that could end up sav

He was using <b> instead of <div> because it was shorter. That's a 4 byte savings on each button. If you had a lot of buttons on a page...that could end up saving hundreds of bytes. I'm not sure how much that matters in the long run, but it's a great attitude to have. Bytes matter, microseconds count. I started this comment purely tongue-in-cheek, but convinced myself of the argument before I finished writing it.