WWOOF originally stood for "Working Weekends on Organic Farms" and began in England in 1971.
Sue Coppard, a woman working as a secretary in London, wanted to provide city folks with access to the countryside, while supporting the organic movement.

Her idea started with trial working weekends for four people at the bio-dynamic farm at Emerson College in Sussex. People soon started volunteering for longer periods than just weekends, so the name was changed to Willing Workers on Organic Farms.

However, the word "work" caused problems with some countries' labour and immigration authorities, who confused WWOOF volunteers with migrant workers. Because of this, and in recognition of the worldwide nature of the organization, the name was changed again in 2000 to World Wide Opportunities on Organic Farms, though some WWOOF groups chose to retain the older name. (Wikipedia)

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