File Processing - Building Java Programs: A Back to Basics Approach - page 375

Did You Know?
Origin of Data Processing
The field of data processing predates computers by over half a century. It is often
said that necessity is the mother of invention, and the emergence of data process-
ing is a good example of this principle. The crisis that spawned the industry
came from a requirement in Article 1, Section 2, of the U.S. Constitution, which
indicates that each state's population will determine how many representatives
that state gets in the House of Representatives. To calculate the correct number,
you need to know the population, so the Constitution says, “The actual
Enumeration shall be made within three Years after the first Meeting of the
Congress of the United States, and within every subsequent Term of ten Years, in
such Manner as they shall by Law direct.”
The first census was completed relatively quickly in 1790. Since then, every
10 years the U.S. government has had to perform another complete census of the
population. This process became more and more difficult as the population of the
country grew larger. By 1880 the government discovered that using old-fashioned
hand-counting techniques, it barely completed the census within the 10 years
allotted to it. So the government announced a competition for inventors to pro-
pose machines that could be used to speed up the process.
Herman Hollerith won the competition with a system involving punched
cards. Clerks punched over 62 million cards that were then counted by 100
counting machines. This system allowed the 1890 tabulation to be completed in
less than half the time it had taken to hand-count the 1880 results, even though
the population had increased by 25 percent.
Hollerith struggled for years to turn his invention into a commercial success.
His biggest problem initially was that he had just one customer: the U.S. govern-
ment. Eventually he found other customers, and the company that he founded
merged with competitors and grew into the company we now know as
International Business Machines Corporation, or IBM.
We think of IBM as a computer company, but it sold a wide variety of data-
processing equipment involving Hollerith cards long before computers became
popular. Later, when it entered the computer field, IBM used Hollerith cards for
storing programs and data. These cards were still being used when one of this
book's authors took his freshman computer programming class in 1978.
in a file called hamlet.txt . A file name often ends with a special suffix that indi-
cates the kind of data it contains or the format in which it has been stored. This suffix
is known as a file extension. Table 6.1 lists some common file extensions.