programming-for-dummies

Chapter 8: Reading
and Saving Files
In This Chapter
Storing data in text files and database files
Storing your fixed size data in random-access files
Storing your varying size data in untyped files
Almost every program needs to save data. Spreadsheets need to save
numbers and formulas, word processors need to store text, databases
need to store names and addresses, and even video games need to store the
top ten highest scores.
To save data, programs store information in a file. After a program stores
data in a file, it eventually needs to open that file and retrieve that data
again. To save data in files, programs generally use one of four methods:
✦ Text files
✦ Random-access files
✦ Untyped files
✦ Database files
Storing Data in Text Files
A text file, sometimes called an ASCII or plain text file, contains nothing but
characters, such as letters, numbers, and symbols.
Text files only store actual data, such as names and addresses, but don’t
contain any formatting information, such as fonts or underlining. Because
text files only contain data, they represent a universal file format that any
computer, from an ancient Commodore-64 to a Cray super computer, can
read and use.
Text files typically store data as one long string of data like this:
Joe Smith 123 Main Street New York NY 10012