From Istaria Lexica

Template documentation (for the template shown above, sometimes hidden or invisible)
This template is a shorthand for <div style="clear:both;"></div>.
It moves any content following the template below any objects floating to the left and/or right (TOCs, infoboxes, images, etc..).
Type {{clr}} in an article at the point you want the clear.

Visit Clr/doc to edit this text. (How to: document correctly)