Pharrell Williams has launched a Happy campaign for young readers.

The singer has partnered with FirstBook, a literacy charity, to donate up to 50,000 books to children in low-income families in the US.

Pharrell’s publisher, Penguin Young Readers, announced that the Twitter hashtag #readHappy had been established for fans to post thoughts or images on why reading makes them “Happy.”

Every post shared elsewhere on social media will lead to a donation.

Pharrell said: “Every child on this planet deserves to experience the joy of reading.”

Pharrell’s picture book, Happy, based on his hit song, comes out in the US on October 6.