There are lots of articles and books on data normalization. They usually scare people including me. I am not going to get into a theoretical discussion of the pros and cons of data normalization levels. This differs depending on the database used, so the more you understand how to manipulate data in Access, the more obvious the way you should store data in tables and fields. A primary goal of good database design is to make sure your data can be easily maintained over time.
Databases are great at managing more records.
They are terrible if fields need to be added since all its queries, forms, reports, and code are field dependent. Spreadsheet Gurus Data normalization is a particularly difficult concept for spreadsheet experts. Having been a spreadsheet developer prior to using databases, I sympathize with those struggling to make the transition. The main reason you're using a database rather than a spreadsheet is probably because have so much data you can't manage it properly in Excel. The fundamental advantage of a database is that it allows your data to grow without causing other problems.