[GENERAL] ST_Intersects vs. ST_Touches

[cyw]

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_