One of the more intriguing guests at this year’s literary festival is that of Keith Stuart. Keith, who is appearing alongside Richard Roper at Salisbury Playhouse on Saturday morning at 11.30am, is the Guardian’s gaming correspondent by day, and a bestselling novelist by night. He combined both of these in his funny and warm-hearted debut, A Boy Made Out of Blocks, which was both a Richard and Judy pick and has sold over 250,000 copies to date.

The starting point of Keith’s book were his experiences with his own son, Zac. Zac was diagnosed as being on the autism scale when he was seven and struggled with many of the daily challenges that parents in a similar situation will recognise. But where Zac came alive was through playing the computer game Minecraft: here he was happy and engaged, and able to respond and articulate in a way his parents hadn’t seen before. Keith used these experiences as an inspiration for his fiction – a personal story that has gone on to strike a chord with many parents.

Back when I was growing up, computer games came in a somewhat more rudimentary form. I still remember the likes of Pong, a minimalist (ie rubbish) black and white animation where you played a sort of slow-motion version of table tennis, with two sticks sliding up and down the screen. My parents, who wanted our family computer to be educational, spurned such machines as the ZX Spectrum and the Commodore 64 for the well-meaning but limited BBC Micro 32K. The machine was so slow, loading games by cassette would take up to half an hour. And when they did finally load up, they would inevitably crash.

It’s sometimes suggested that computer games haven’t changed very much since those early days: the graphics might be better, but you’re still essentially shooting things or solving puzzles or kicking balls around. I must confess to thinking like that, too, until my daughters successfully petitioned to get Minecraft for Christmas last year. Minecraft is just, well, different. Is it even a game in the traditional sense? To my layman’s eye, it’s a little bit more akin to Lego – where players build and create and explore new worlds. The planning and invention involved can be remarkable – a far cry from the oft-repeated media message that computer games are turning our children into zombies and killers.

Like most families, children and screen time is a long running battle in our household. But it isn’t always bad – as the creativity of Minecraft can show.

Keith Stuart and Richard Roper are appearing at Salisbury Literary Festival on Saturday, October 19, 11.30am at Salisbury Playhouse. Tickets via salisburyliteraryfestival.co.uk