The first one is Etymology of word "Dayak" :
~According to Lindblad, Dayak word comes from the power of Kenyah language, which means the upstream [river] or inland.
~~As with the King, who argued Dayak may also be derived from the word aja, a Malay word meaning native or indigenous.
~~~In Commans opinion's, Dayak means human.
Dayak comprises more than 200 riverine and hill-dwelling ethnic subgroups.
Next, about some Dayak culture :
* Hunting down the head
* Gawai Dayak
* Burial traditions
* Agriculture