Great question! You see finger print scanners on lots of devices these days – including mobile phones.

Secret codes are a great way to keep things private and safe, as you’ll know if you have a combination lock on your diary or bike!

Human beings are lucky because every single person alive has their own, totally unique secret code – on their fingers and thumbs!

Find out more about eyes at: www.funkidslive.com/learn/techno-mum

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Techno Mum's Tech Line with support from the Institution of Engineering and Technology.