Kateb are the religious scriptors related to Abrahmic Religions. The Abrahmic Religions are refered to as revealed Religions and Have their holy books and are also refered to as the religions of the book. All the three religions have same prophets in the begining.
Judaism=Old Testament. Christianity=Bible. Islam=Quran.
Gurbani refers to these books as Kateb.
Dr. Samir Singh said that Kateb references to Koran, Bible Torah & Zend Avesta.
Conclusion - Mostly granths which originates in west side in arabian countries together are known as Kateb or Katebas