ST_Intersects vs. ST_Touches

What are the differes between ST_Intersects and ST_Touches?
The 1st query return something, but the 2nd return 0.

select road.link_id from road where
Intersects (
Buffer(GeometryFromText('POINT(-88.02083 41.956982)',4326), .001),
the_geom
)

select road.link_id from road where
Touches (
Buffer(GeometryFromText('POINT(-88.02083 41.956982)',4326), .001),
the_geom
)

Thanks.
_CYW_