The Book of Changes is the divination manual and cosmology of the sixty-four hexagrams. The Book of Documents, or Shangshu, collects speeches, harangues and pronouncements attributed to rulers and ministers from the legendary sage kings down through the Zhou; its genuine chapters contain some of the oldest sustained Chinese prose in existence, and they are famously hard to read. The Book of Songs, also called the Odes, holds 305 poems, folk songs about courtship, harvest and grievance alongside court hymns and dynastic praise, and was the shared literary currency of the Zhou elite, quoted in diplomacy to make points obliquely.
The Book of Rites, or Liji, is a Han compilation of material on ceremony, mourning, education and conduct, uneven in date and origin, and important later because two of its chapters were extracted to become the Great Learning and the Doctrine of the Mean. The Spring and Autumn Annals is a bare chronicle of the state of Lu from 722 to 481 BCE, so terse it is almost unreadable alone; tradition held that Confucius edited it and encoded moral verdicts in his choice of words, and it is transmitted with commentaries, above all the Zuozhuan, which supply the narrative the chronicle omits.
A sixth text, the Classic of Music, appears in early lists and then disappears. Whether it was destroyed under the Qin, or never existed as a separate book, or survives in altered form as the Record of Music chapter of the Liji, cannot be settled from the evidence available.
Confucius is traditionally said to have edited all of them. The material is largely older than he is, and the editing claim is a later attribution rather than a documented fact.