The sectionhiker.com blog has a brief overview:

It is a repetition injury often caused by hiking or running and presents itself as chronic heel pain. This pain is caused by the inflammation of the ligament that connects your heel bone to the ball of your foot.

I’ve found that the best way to cure plantar fasciitis is to simply stop hiking for an extended period of time, like over the winter, AND to get a pair of boots with better arch and heel support.

I can’t recall having linking to this blog, which has a wealth of info for lightweight backpackers and thru-hikers. Definite bookmark/feed list potential.

(Hat tip: The Sock Site’s hiking blog page).