The word ‘Veda’ means knowledge that is directly revealed by the Lord. In the beginning, there was only one Veda, the Yajur Veda, all the verses with explanatory and historical texts were together in one whole body. To easily locate a particular subject, the highly qualified Vyasadeva, divided the Vedas into four. “Srila Vyasadeva separated the mantras of the Rg, Atharva, Yajur and Sama Vedas into four divisions [SB 12.6.50]”. He did not create a new composition; he condensed that abridged portion.
The Puranas were produced from the original Veda. They are faithful to Veda and are also known as supplementary Vedic literature. Because sometimes in the original Vedas the subject matter is too difficult for the common man to understand, the Puranas explain matters simply by the use of stories and historical incidents. The Upanisads call them the fifth Vedas. Five thousand years ago, Srila Vyasadeva composed the Puranas. He did not create the Puranas and Itihasas, histories. Vyasadeva is known as a transmitter, not as an author.
Source: A.C. Bhaktivedanta Swami Prabhupada (2012 edition), “Teachings of Lord Caitanya, The Golden Avatara”, Page 305
Rasamandala das (2014 edition), “Islam and the Vedas – Lost Harmony”, Page 111, 112 & 114