Normalization is the process of efficiently organizing data 
in a database. There are two goals of the normalization 
process: eliminate redundant data (for example, storing the 
same data in more than one table) and ensure data 
dependencies make sense (only storing related data in a 
table). Both of these are worthy goals as they reduce the 
amount of space a database consumes and ensure that data is 
logically stored.

First normal form (1NF) sets the very basic rules for an 
organized database: 
? Eliminate duplicative columns from the same table. 
? Create separate tables for each group of related data and 
identify each row with a unique column or set of columns 
(the primary key). 
Second normal form (2NF) further addresses the concept of 
removing duplicative data: 
? Meet all the requirements of the first normal form. 
? Remove subsets of data that apply to multiple rows of a 
table and place them in separate tables. 
? Create relationships between these new tables and their 
predecessors through the use of foreign keys. 
Third normal form (3NF) goes one large step further: 
? Meet all the requirements of the second normal form. 
? Remove columns that are not dependent upon the primary 
key. 
Finally, fourth normal form (4NF) has one additional 
requirement: 
? Meet all the requirements of the third normal form. 
? A relation is in 4NF if it has no multi-valued 
dependencies