When you are buying online you usually get the option to see the items you searched for ordered by price, average customer rating, or perhaps date. If you have ever tried to put a bunch of things (e.g. books on your shelf) in order, you'll know it takes time. This is why the world owes a huge debt of gratitude to computer scientist Tony Hoare for inventing Quicksort — a famous sorting algorithm which celebrated its 60th birthday this year.

Tony Hoare, the inventor of Quicksort, in 2011. Photo: Rama, CC BY-SA 2.0 FR

Hoare developed Quicksort long before online shopping had even been conceived of, but it's still hailed as one of the best sorting algorithms and implemented in many programming languages and libraries. Its anniversary was celebrated at the Isaac Newton Institute for Mathematical Sciences (INI) in Cambridge this year.

On that occasion we were lucky enough to (virtually) met Hoare to ask him about his most famous brain child, whose invention started on a couch.

To find out more about this, and the beautiful algorithm itself, carry on reading here.

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This article is part of our collaboration with the Isaac Newton Institute for Mathematical Sciences (INI), an international research centre and our neighbour here on the University of Cambridge's maths campus. INI attracts leading mathematical scientists from all over the world, and is open to all. Visit www.newton.ac.uk to find out more.