Database

Database is the store where related data is stored at, so that the computer programs can easily select or edit programs.

Database is handled by software, which must be able to create, retrieve, update and delete the data in the Database.

A Serial File is a file of items that are stored together as a series, one after another, to ease the writing of a program to find an item in the file.

A Sequential File is a Serial File which stores the items in order.
A Sequential File can also accessed using an index, which is a separate file, where the software looks up the position of the item in the index and goes straight to the part of the file where the required data is, then does a serial search there. These files are called Indexed Sequential Files.

Flat File Database is Database consisting only one table. It's made from fields ( a characteristic of something stored in a database) and  records ( all the data about one item in a database).

A Field Key is the key field that we have to look back at on every record.