Donatello is the brains of the team and a natural mechanical wizard when it comes to technology or fixing things.
Donatello is the most scientific minded turtle, and is responsible for the creation of most of the Turtles' high-tech equipment, including the Turtle Van, the Turtle comms, and the Turtle Blimp. He also managed to build a working inter-dimensional portal though it is unknown how he found the necessary equipment to do so. He also thwarted a super knowledgeable Slash without any assistance. He wears a purple bandana and, as with his other incarnations, he carries a Bo staff. He is voiced by Barry Gordon. The running gag in the show was that Donatello's inventions usually had the habit of breaking down or blowing up in his face, although there were many times the team relied on him whenever they were faced with scientific or mechanical problems.
The 1987 series briefly hinted of Donatello's vocal reluctance to the group's role as crime fighters and helping humans in particular, both in the five pilot episode and a plot point in the "Red Sky" episode Cry H.A.V.O.C.!. He seemed to be the least interested among his brothers towards human culture, and even reflected if being a normal turtle would have given them a much easier life. Despite this, it never deterred him from appreciating human food such as pizza, and even bothered to get himself a college degree through mail. In the rare moments when Leonardo was kidnapped or incapacitated, Donatello usually takes on the role as the group leader.
In the film Turtles Forever, he is the one who created the Trans-dimensional Portal Stick in order to reach the Turtle Prime Universe. When his skeptical 2003 counterpart (whom he fondly nicknamed "Mr. Wizard") voiced his concerns over calling a wrench a hammer, Donatello replied that science is more than just facts and details.
He and the other members also appear in the 2012 serires, first making a brief cameo in Wormquake! and then The Wrath of Tiger Claw. Unlike Turtles Forever, he and the other characters are voiced by their original voice actors. They all then appear in Trans-Dimensional Turtles.