1NF, or First Normal Form, is a property of a relational database table that ensures data is organized in a way that eliminates duplicate entries and maintains atomicity. This means that each column in a table must contain only indivisible values, and each entry in a column must be of the same data type. To achieve 1NF, a table must also have a unique identifier, known as a primary key, for each row. This structure helps to prevent redundancy and ensures that each piece of data is stored in a clear and organized manner, making it easier to manage and query the database.