The information about each person, place, or thing is called a record. If you have a data base that lists the names, addresses, and phone numbers of all your clients, and you have 42 clients, there are 42 records in your client data base. Each category of information you keep track of is called a field. If your address-book data base includes the name, address, phone number, and birthday of each friend, you have four fields in that data base.

Figure 5-4
Records and fields

The tedious part of using a data base application is typing all the information when you set up a new data base. The fun part is using the application to search for a particular piece of information or to rearrange the information according to criteria you specify.

Sometimes it's useful to know every detail about everything in your data base, but most of the time you want a subset of the information—all your clients with birthdays in December, a list of students who scored more than 6K) on their SATs, a list of customers who spent more than $2000 on shoes last year and you don't care about the other information that's in the data base.

These subsets are called reports. You can generate hundreds of different reports from one data base without affecting the information in the data base as a whole.

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Chapter 5: Application Programs