What div tag refers to?

Answer 1

Basically div tag forms a block of code in your while program. you can do things exclusively to this block without affecting the entire code like changing the background colour.

Answer 2

the div is a container. it allows you to apply css codes to the code inside the div tag. if you apply a border or background to the div it will look like a block on your webpage. any text you add before or after the div tag would display on another line and not "inline" with the text in your div tag.