Meanings of alliterative verse in English

The question arises-Whatis the nature of the cadence in alliterative verse?

Next come the epic poems of Cynewulf, Crist, Juliana, Elene, and Andreas, also written in alliterative verse.

Two hundred years later, when The Vision of Piers the Ploughman was first printed, the printer in his preface explained alliterative verse very well.

The forms of words embodied in charms and incantations were originally intended to be sung, and usually contained some rhyme, jingle, or alliterative verses.

I must re-read St Aldhelm and the Venerable Bede.... Now, I ask, do you expect me-me, with my head full of Aldhelm's alliterative verses-