A database document is just a collection of information stored in computerized form. The simplest way to understand a database is to think of it like a set of 3 x 5 cards. Since the information is on your computer, though, a dick of the mouse or the stroke of a key can alphabetize those “cards,” or find just the names of the people on the cards who live in a certain town, or tell you who owes how much money, and so on.
Computer databases can be highly structured, storing the same kind of information about each item in the database in well-defined compartments. This works as if you printed a standard form on each of your 3 x 5 cards perhaps with one space for a name, one space for an address, and one space for a telephone number. In a structured computer database, the “space” for a name, a part number, a price, is called a field. A record corresponds to one of the individual 3 x 5 cards. The record contains a complete set of fields, all filled with information corresponding to a particular item: if your database is a name-and-address list, each record represents a person; if your database is a parts catalog, each record represents one part.
A specific set of fields and records organized in a specific order, including the information they contain, is called a table. In fact, tables are often displayed on the screen with each item, or record, in a row, and each field as a column.
Structured databases can be either flat file databases or relational databases. In a flat file database, you can work with only one data table-one set of fields-at a time. In a relational database, you can use multiple tables (multiple database documents) at once. Flat file databases are much easier to understand and use, but relational databases are much more efficient for many things you commonly do with data, especially in businesses.
A database can also be simply a free-form collection of information, without any particular structure. In this case, the analogy would be to a pile of notes you’ve written on whatever paper was handy at the time the information on each piece of paper doesn’t have to be organized in the same way.
The term database can also refer to the software package itself that you use to create the database. More often, the software is called a “database program” (“database application” is more specific) or a “database management system” (DBMS).
A database application is one of the most useful tools on the computer, and is actually an incredible amount of fun.