Popular music is a "lingua franca" for young people. The songs of German "Liedermacher" lend themselves to classroom uses. "Liedermacher" are cultural commentators who entertain and edify with their songs. Focusing on social and political aspects of postwar Germany, "Liedermacher" songs have been a "gesungene Landeskunde" resource since the early 1960s. Some songs took a retrospective view of the 20th century, e.g. Degenhardt's "Zeit-Zeuge Jahrgang 00," Mey's "Das Foto vor mir auf dem Tisch", and Wader's "Familienerbe". Each of these three songs takes personalized stock of a dense century as history "von unten," each with a strikingly distinct voice accompaniment.