proper db standard

I am creating a simple database that will hold information about various publications. There are keywords that are associated with these publications and there can be anywhere from 1 to about 6 of these different keywords.

As I see it I have two choices:

1) create keyword fields 1-6 in the publications database and accept that some of these fields will be empty.
2) create two tables: "publication" and "keyword". In this scenario I have no limit on the amount of keywords that are used and I don't have empty fields. However, many of the keywords repeat for different publications. In this situation I would have some repeating words in the columns.

I lean toward #2 but wanted to see if there was a preferred standard or another possibility that I am overlooking??

Thanks
Jodi

_______________________________
Jodi L Kanter
BioInformatics Database Administrator
University of Virginia
(434) 924-2846
jkanter(at)virginia(dot)edu