"wide" at the end of id?

Hi,
I am learning css and html, and i am taking apart a free template i found and cant find an answer to this entry:

#contentwide {line-height:1.5em; margin:10px 0 10px 160px; padding:0; text-align:left;}

there is an id called #content (without the “wide”)
it is used a few times in the css file, but there is no reference to it in the html. What does it mean? where can i get more info on this?

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