This file contains additional information, probably added from the digital camera or scanner used to create or digitize it.
If the file has been modified from its original state, some details may not fully reflect the modified file.
October 14, 2014
Luis Von Ahn explains why growing up in Guatemala led him to keep Duolingo's services free to give poorer people the opportunity to improve their lives.
Telegraph.co.uk and YouTube.com/TelegraphTV are websites of The Daily Telegraph, the UK's best-selling quality daily newspaper providing news and analysis on UK and world events, business, sport, lifestyle and culture.