Database normalization is designing a relational database schema that reduces data redundancy and improves data integrity. There are several levels or forms of database normalization, each with its rules and criteria. The four most common types of database normalization are: First Normal Form (1NF): A table is in 1NF if it has no repeating groups or arrays of values within a single record. Each attribute (column) should contain only atomic values (single values that cannot be further decomposed). Each record (row) should be unique and identified by a primary key (one or more attributes uniquely identifying a form). Second Normal Form (2NF): A table is in 2NF if it is in 1NF and has no partial dependencies. A partial dependence occurs when an attribute depends on only part of the primary key rather than the whole key. For example, if a table has a composite primary