What is DATA ACCESS OBJECT (DAO) - It is a object/interface, which is used to access data from database of data storage. WHY WE USE DAO: To abstract the retrieval of data from a data resource such as a database. The concept is to "separate a data resource's client interface from its data access mechanism."

What was the DAO used for?

In computer software, a data access object (DAO) is a pattern that provides an abstract interface to some type of database or other persistence mechanism. By mapping application calls to the persistence layer, the DAO provides some specific data operations without exposing details of the database.

What is DTO and DAO in Java?

DTO is an abbreviation for Data Transfer Object, so it is used to transfer the data between classes and modules of your application. DAO is an abbreviation for Data Access Object, so it should encapsulate the logic for retrieving, saving and updating data in your data storage (a database, a file-system, whatever).