Season
- Season 0 1998-12-27
- Season 1 1970-01-01
- Season 2 1970-01-01
- Season 3 1970-01-01
- Season 4 1970-01-01
- Season 5 1970-01-01
- Season 6 1970-01-01
- Season 7 1970-01-01
- Season 8 1970-01-01
- Season 9 1970-01-01
- Season 10 1970-01-01
- Season 11 1970-01-01
- Season 12 1970-01-01
- Season 13 1970-01-01
- Season 14 1970-01-01
- Season 15 1970-01-01
- Season 16 1970-01-01
- Season 17 1970-01-01
- Season 18 1970-01-01
- Season 19 1970-01-01
- Season 20 1970-01-01
- Season 21 1970-01-01
- Season 22 1970-01-01
- Season 23 1970-01-01
- Season 24 1970-01-01
- Season 25 1970-01-01
- Season 26 1991-12-26
- Season 27 1970-01-01
- Season 28 1993-12-26
- Season 29 1970-01-01
- Season 30 1970-01-01
- Season 31 1996-12-26
- Season 32 1970-01-01
- Season 33 1970-01-01
- Season 34 1970-01-01
- Season 35 1970-01-01
- Season 36 1970-01-01
- Season 37 1970-01-01
- Season 38 2003-12-26
- Season 39 2004-12-16
- Season 40 2005-12-25
- Season 41 2006-12-25
- Season 42 2007-12-23
- Season 43 2008-12-28
- Season 44 2009-12-21
- Season 45 2010-12-28
- Season 46 2011-12-27
- Season 47 2012-12-26
- Season 48 2013-12-28
- Season 49 2014-12-29
- Season 50 2015-12-28
- Season 51 2016-12-26
- Season 52 2017-12-26
- Season 53 2018-12-26
- Season 54 2019-12-26
- Season 55 2020-12-28
- Season 56 2021-12-28
- Season 57 2022-12-26
- Season 58 2023-12-26
- Season 59 2024-12-29
Royal Institution Christmas Lectures - Season 41 Episode 4 The case of the uncrackable code
5.10 60 minutes From the Caesar Cipher to the Da Vinci Code, people have been fascinated by secret messages. The mathematics of codes lets us to do everything from photographing the surface of Mars to shopping securely on eBay. Find out how prime numbers are now the key to codes which protect credit cards from internet hackers, and how, in the digital age, i-pods and digital TV are just a load of 0s and 1s.
