The homepage widget displays a block at the top of the homepage. It’s a useful place to introduce you and your business but to honest it’s not that important. People will be visiting your site because they want something. The homepage showcase does just that on it’s own. If they want to find out a bit more about you then an ‘About Us’ page does that.
However, if you want to add an introduction to your site you can do this with a widget. Go to Appearance > Widgets and add a Text widget to the Homepage Top widget area.