This article is from the Hiking Boots FAQ, by Chris Gilbert email@example.com with numerous contributions by others.
A 4 season boot is one that is designed for all-year-round use but,
in that it is suitable for winter walking, it is likely to be too
heavy and warm for comfortable summer walking. A good 3 season boot
will cope with non-extreme winter walking and, if stiff enough, will
take a walking crampon while still being light enough to be
comfortable in all but the hottest weather.