Why do people walk?

The 2001 National Household Travel Survey reports the following walking trip purposes:

Trip Purposes as Percentage of Walking compared to Other Modes, 2001
 Percentage of Walking TripsPercentage of Other Modes
Social and Recreational44.726.6
Personal Family Business36.043.8
School or Church11.09.8
To/From Work or other Work/Business related6.618.8
Other1.50.8

The Omnibus Survey completed for the Bureau of Transportation Statistics in February 2003 asked all respondents for what purpose they walk, run, or jog:

PurposePercentage (weighted)
Commuting to work or school6.18
Recreation10.30
Exercise/for my health60.35
Personal errands (to the store, post office, walking the dog, and so on)19.42
Required for my job3.75

People also walk bcause of the many benefits of walking.