Normal form definitions
@A_V, I think you can find what you're looking for here. It has explanations of 1NF - 4NF, including BCNF.

From the page:


  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.
  
  The Boyce-Codd Normal Form, also referred to as the "third and half (3.5) normal form", adds one more requirement:
  
  Meet all the requirements of the third normal form.
  Every determinant must be a candidate 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.
  
  Remember, these normalization guidelines are cumulative. For a database to be in 2NF, it must first fulfill all the criteria of a 1NF database.