Prelude: Computing from Ancient Times to the Modern Era - The Technical and Social History of Software Engineering - page 16

Table 1.2 Evolution of Recording Methods and Media
As can be seen from Table 1.2 , the recording of information is an ancient activ-
ity that dates back about as far as the invention of writing and numerals. Without
a method of recording the information, calculations or ownership of articles could
not be shared with others or used later to verify transactions.
A modern problem that will be discussed in later chapters is the fact that storage
methods are not permanent and there is uncertainty about how long either paper
records or computerized records might last.
Paper is flammable and also affected by insects, moisture, and other forms of
destruction. Magnetic memory is long lasting but not permanent. What's worse is
that any kind of stray magnetic field can damage or destroy magnetic records.
Optical records stored on plastic disks might last 100 years or more, but the
plastic itself has an unknown life expectancy and the recording surfaces are easily
damaged by abrasion, soot, fire, or mechanical stress.
The bottom line is that the earliest known forms of records, such as carvings on
stone or clay, probably have the longest life expectancies of any form of recording
yet invented.
Communicating Information
Table 1.3 lists the inventions for how information can be transmitted or shared
with other human beings once calculations have been performed and the results
stored in some fashion. It is obvious that almost all information will be needed by
more than one person, so communication and information sharing are almost as
old as mathematics.