+9  A: 

I believe it's a bookmark - it serves to let you find a particular bit of code again later.

Edit: it is indeed - see: http://msmvps.com/blogs/vipul/archive/2006/01/20/Visual-Studio-Bookmarks.aspx

Eamon Nerbonne  2009-08-12 08:50:19
+3  A: 

yes it's a bookmark, and it's very useful when you want to move between your code, to set a new bookmark use ctrl+k +k shortcut to move between bookmarks use the following: ctrl + k + n to move next ctrl + k + p to move previews

to remove the bookmark press ctrl + k + k again on the same line.

Wael Dalloul  2009-08-12 08:53:35

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