Little is known about the
giants of Draenor, other than the facts that they lived on the world of Draenor and were of giant size. Its skeleton is human-like but very, very big (the size of a building or larger as seen in , Warcraft II , and Warcraft III ).
World of Warcraft
In Warlords of Draenor This section concerns content exclusive to . Warlords of Draenor
Bones of Agurak at Agurak's Fall
BlizzCon 2013, indicated that the giants of draenor may have been related to gronn and ogres. From concept art, these giants may be really big gronn.
The bones of these giants can be seen forming the
Thunderlord clan's city of Grom'gar at Colossal's Fall and the Bones of Agurak lying in the desolation of Agurak's Fall. They are found in central region and at the eastern edge of Frostfire Ridge.
Temple of the Damned
This section concerns content exclusive to . Warcraft II: Tides of Darkness
Warcraft II, the Temple of the Damned structure was said to be constructed from the bones of these giants.  ( W2man 84) These structures would later be used by the Scourge and Forsaken in the Undercity.
In Warcraft RPG This section concerns content exclusive to the Warcraft RPG, and thus unlikely to be canon.
says that the ogres are one of the last races of Draenor's giants, implying that there has been more than one race of giants that have lived on Draenor. Horde Player's Guide  ( HPG 156)
This article or section includes speculation, observations or opinions possibly supported by lore or by Blizzard officials. *
These creatures may very well be related to the
gronn, the lords of the ogre race, and perhaps all races of Draenor's giants may be related distantly. They are referred to as "Grom" in Orcish.