Someone who is an utter twat. Stupid beyond belief.
This orignates from the GCSE course DiDA which pupils absolutely hate. Therefore, the insult DiDA was made to compare the person described as the most tedious and boring ICT course in the world.
An absolutely foolproof way to keep minors from viewing content deemed "too mature" for them to watch.
Billy: "So I was trying to watch some videos for an M rated game, and I ran into an age gate, so I put in my real birthday. SOMEHOW it managed to figure out that I am 12. CURSE YOU AGE GATE!!!"
Bill: "Fucking age gate! *quick scroll* THERE! I was born on January 1, 1904. Fuck you age gate."