I am standing in an amazing little shop in Highgate High Street, in Highgate, London. It sells all kinds of things: clothes, shoes, books, games, plates, and jewellery. Most of the things in the shop are used It's a charity shop. There are thousands of charity shops in the UK. What are they? Well people donate things to these shops and the shop sells them and gives the money to good causes. The people who workhere are all volunteers. Mary farmer is working here today.