The children's television show that has made characters such as Cookie Monster, Elmo and Big Bird familiar across the world has turned 40.

Sesame Street is shown in 140 countries, and has helped teach millions of children the alphabet and how to count.

It teaches children in some countries life-saving tips, such as basic hygiene, while in others it discusses issues such as HIV and Aids. 
Cath Turner reports from New York.

Source: Al Jazeera