From various dnd languages list mainly the giants were speaking this giant language. Actually, this giant language 5e, known as jotun by the speakers who speaks it, basically it was the ancient language for most of the giants. It was one of the oldest and active languages. It normally believed that the language has been shared some of its roots by the common and also the thorass.
This d&d giant language has its own script. Both the ancient and also the modern giant had written by the dethek runes. The ancient giants were also had the set of logographic runes primarily used for the runecasting. Even though they were also used this language with symbolically in an art for representing or refer to the related giant subraces and also the gods.
Normally, they were not truly an alphabet or the syllabary, but rather than the diagrams or the models for the sake of relationships in between the cosmic forces and also the deeper truths of the universe.