A blogroll is a collection of links to other weblogs. When present, blogrolls are often found on the front page sidebar of most weblogs.
Various weblog authors have different criteria for including other weblogs on their blogrolls. These range from matters of common interest to frequency of updates and posts to country/geographical/communal relations to link exchange policies. Some blogrolls also simply consist of the list of weblogs an author reads him or herself, and some news aggregators allow their users to export that list directly to a weblog.
With the advent of syndicated newsfeeds, even blogrolls can be, and are being, syndicated. OPML is one of the popular ways to syndicate a blogroll in case a weblog author wants others to be able to access the weblogs in his/her blogroll. [wikipedia]