Daniel Witwicky is a young member of the Witwicky family. He is most often portrayed as the son of Spike and Carly, but was once portrayed as the son of Spike's brother Buster Witwicky. Daniel often gets into trouble, which requires either his father or the Autobots to save him. He is very good friends with the Autobots, particularly Wheelie, Grimlock, and Hot Rod, but the one he's closest to is Arcee, who views him as a surrogate son.
Daniel is (sometimes) a Headmaster partner, and sometimes he is a Titan Master named Leinad, both in conjunction with Arcee.
Personality
Daniel seems to be a level-headed boy, and he is capable of teaming up with the autobots with missions to defeat the decepticons. He works well with Arcee, and they are both usually partnered up together, with Daniel in his exo-suit, entrusted to him by Arcee. This suit was from a space shuttle, in which his father, Spike Witwicky, would use, when there is a need for an emergency escape.
He is also friendly and very trustworthy in the eyes of Optimus Prime, which caused him to gain the liking of several autobots like Hot Rod and the leader of the dinobots, Grimlock.
Trivia
Daniel has a crush on Arcee as shown in the season 4 3-part episode "Rebirth" as he became her Headmaster partner and has feelings for her.
He and his parents made a few appearances in Transformers Animated.
In IDW continuity, "Daniel" is the first name of Sparkplug Witwicky, the grandfather of this Daniel.