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![Mahmoud Nasser](https://secure.gravatar.com/avatar/e0b82d949bda66292679b3fc5329ae7b?s=96&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
Mahmoud Nasser
5,507 Pointsstring concatenation
bookmarksResults.innerHTML+='<div class="well">'+
'<h3>'+name+
'<a class="btn btn-default" target="_blank" href="'+url+'">visit</a>'+
'<a onclick="deleteBookMark(\''+url+'\')" class="btn btn-danger" href="#">Delete</a>'+
'</h3>'+
'</div>';
i dont understand the concatention in the deleteBookMark function call any help please
2 Answers
![Steven Parker](https://uploads.teamtreehouse.com/production/profile-photos/969492/micro_tool_chess_set_2.jpg)
Steven Parker
230,688 PointsConcatenation is just joining strings together to make a longer one. In this example, it is used in part to make a string using the contents of variables, but it is also being used just to keep the code line from being really long.
![Mahmoud Nasser](https://secure.gravatar.com/avatar/e0b82d949bda66292679b3fc5329ae7b?s=96&d=https%3A%2F%2Fecs-static.teamtreehouse.com%2Fassets%2Fcontent%2Fdefault_avatar-445fbbabfc8dc9188fb5967fe43322ee0c3e0dd1e10f378bf8343784af5a13eb.webp&r=pg)
Mahmoud Nasser
5,507 PointsThanks i got it Steve
Mahmoud Nasser
5,507 PointsMahmoud Nasser
5,507 Pointsi still have a problem in understanding this: deleteBookMark(\''+url+'\')
Steven Parker
230,688 PointsSteven Parker
230,688 PointsNormally, quote marks enclose a literal string. If you want to include a quote mark inside a string you have to do something special. The backslash (\) is known as the "escape character", and when you put it before a quote mark it means that quote mark is part of the string and does not indicate the end of it. The other quote mark that follows the first one does end the string. Then the
+url+
part just joins whatever is in the "url" variable to the string, and then joins that onto the next string (which also has an escaped quote mark).Here's a simpler example: