A sample driver is a software component that allows an application to access and manipulate data stored in a database. It serves as an interface between the application and the database, providing methods for querying or updating specific fields within records in the database. The sample driver retrieves information from the database based on criteria specified by the user, such as selecting certain columns or filtering results based on specific conditions. This allows users to efficiently extract data from a large dataset without having to manually write and execute SQL queries each time they need information.