Jo says the language we use in our lists is idiolectal - it reflects our inner selves, whether in our abbreviations, our choice of spelling, in-words, jokes etc. Her interest some would say obsession with lists extends to her collecting other people's shopping lists discarded in supermarket trolleys to gain what Michael and Jo describe as portholes and portals into people's lives.

Producer: Maggie Ayre

Produced in partnership with The Open University