Examples of style rules.
Need more examples
Two or more osm tags resolve to the same element in the garmin map.
highway=footway | highway=path [0x16 level 1]
This is exactly the same as writing the two lines:
highway=footway [0x16 level 1] highway=path [0x16 level 1]
Space and new lines don't matter except to separate words that have to be separate. You can add as much space and as many newlines to the rule to make it look good. Or remove them depending on taste. For example the following two rules are exactly the sam:
highway = primary | highway=primary_link [ 0x2 level 3 ]
highway=primary|highway=primary_link[0x2 level 3]