The   entity is one of the most common character entity references used in HTML.
When you use the   entity, the characters that follow it are not allowed to break onto a new line.
This is useful for things like addresses, where you might want the city and state to stay on the same line as the street address.
In HTML,   is also known as the "hard space" or "non-breaking space."
It is different from the "normal" space you create when you hit the space bar. The normal space will break if it comes to the end of a line, but the   will not break.
To visualize this, think of the   as a "glue" that keeps words and other characters together.
The   is also used as a way to create extra space between text or other elements on a web page.