Introduction
Song types is here defined as the relation between stanza (verse) and music. To illustrate the different forms we look at the songs of Schubert.
Schubert's song types
Type 1: strophic song
In a strophic song each stanza is set to the same music, so without internal repetitions.
Example: Heidenröslein (Rose on the Heath or Little Rose of the Field), a poem by Johann Wolfgang von Goethe, has been set to music by a number of composers, most notably by Franz Schubert as his "D. 257" for solo voice and piano. Three stanzas and three times the same music.

Type 2: varied strophic song (or modified strophic song)
This type is a variation of the strophic song in which a stanza might have a new melody, new key, new rhythm or varied melodic pattern.

Example: Schubert's "Die Forelle" ("The Trout") Op.32 (D.550) for solo voice and piano. Two stanzas with the same music, the third and last stanza with a different music. This design is motivated by the text. The fisherman, unlikely having much luck in catching the trout - first and second stanza-, has at the end a trick -third stanza-: he muddies the water and catches the trout.


Type 3: declamatory song
In this type there is a speechlike style of singing, following the rhythm of the text. Technically spoken, repetitions of tones are characteristic. One may also have associations with the recitativo.

Example: Schubert's "Wanderer’s Nachtlied", D. 224

Type 4: through-composed song ('durchkomponiert')
A song is said to be through-composed if it has different music for each stanza of the lyrics. Music and words reflect each other.

Many examples of this form can be found in Schubert's "Lieder" such as the famous "Der Erlkönig" (The Erl King), D.328, in which the setting proceeds to a different musical arrangement for each new stanza, portraying the character its own voice register and tonality.
Remarks