Using multiple tables you can avoid the problems faced by creating a flat-file database. A flat file database is a database designed around a single table. containing all the information with fields representing all the parameters. Probelms:
1) A flat file may contain many duplicate fields
2) If you decide that one particular field is no longer necessary or you need to add another field then you are in trouble.
3) If you decide ...
Using multiple tables you can avoid the problems faced by creating a flat-file database. You can learn more about these problems.