856 Subfield $y - Link text:

Subfield $y contains link text which is used for display in place of the URL in subfield $u.  When subfield $y is present, applications should use the contents of subfield $y as the link instead of the content of subfield $u when linking to the destination in subfield $u.  The use of the link text is independent of any decision concerning the second indicator value.

Examples:

856  4#  $uhttp://susdl.fcla.edu/cgi-bin/cgiwrap/ ~fdl/fdlcgi?FA00000011 %2Fjpg$yElectronic resource (JPEG)

856  4#  $uhttp://susdl.fcla.edu/cgi-bin/cgiwrap/ ~fdl/fdlcgi?FA00000011 %2Fpdf$yElectronic resource (PDF)