Tina Johnson from Glasgow says she can't believe no one else had come up with the idea before her.

She told The Scotsman:

"Clients joked about keeping me in the boot and bringing me out to remind them of things when they were practising, so I decided to give them what they wanted."

The DiscDrive CD contains step-by-step instructions for pupils practising in their own car.

Tina added:

"Once this has taken off, my next step will be to bring the CD out in a further six languages to incorporate the huge number of learners from ethnic groups.

"I often have to have an interpreter in the back of the car so there's definitely a need for this on the market."