Celebrity tweeters have taken part in a Twitter contest that seeks to help pupils hone their IT and ethical skills.
Stephen Fry and Sarah Brown, whose identities were kept secret, contributed specially composed tweets to the Twittest contest.
Hundreds of pupils from across Scotland took part in the competition, which was organised by the University.
Participants correctly identified the source of about half of the celebrity tweets.
Pupils had to guess whether tweets had been written by celebrities, teachers, fellow contestants, or had been generated by computer programmes known as chatbots.
Contestants also had to guess whether the authors were trying to hide their real identities.
Contestants mistook Mr Fry for a chatbot about 40 per cent of the time, while pupils thought about one-third of Mrs Brown’s tweets were from a teacher or a chatbot.
The competition was organised as part of the Edinburgh International Science Festival.
It marked the 100th birthday of Bletchley Park codebreaker Alan Turing, who is widely regarded as the forefather of modern computing.
The format is based on the Turing Test, which the scientist devised to show whether a computer can show sufficient intelligence to be mistaken for a human.
Those pupils who were best at spotting fakes or who contributed the best tweets - real and fake - were declared the winners.
Awards were presented at the LateLab T100 Twittest event at the University Inspace gallery.
I congratulate you all on taking part. Alan Turing is one of my great heroes. His mathematical brilliance extended in to the field of thinking about machines and whether or not they could think. Maybe one day machines will be like us – but I think that day is a long way off.