Answer:

In disk files maintained by the company that issues your credit card.

File

Modern commerce (and modern nearly everything else) keeps nearly all its data in electonic form. This data is constantly being updated as computers process new transactions. Periodically, reports and bills are created from this data.

Electronic information is mostly stored in files that are kept in disk storage.

A file is a semi-permanent, named collection of data. A File is usually stored on magnetic media, such as a hard disk or magnetic tape.

Semi-permanent means that data saved in files stays safe until it is deleted or modified.

Named means that a particular collection of data on a disk has a name, like mydata.dat and access to the collection is done by using its name.

A typical desktop computer has one hard disk that can store up to 100 billion bytes of data. This is roughly the equivalent of 100 billion characters. Data on a disk is always organized into files, much as data in a library is organized into books.

QUESTION 2:

When a program stops running, what happens to the data that it has saved in files?