During the mainframe era, software grew to become a major factor of bu
siness, government and military operations. Mainframe software develop
ment favoured the industrialised nations such as the United States bec
ause of the high levels of investment needed for the mainframe compute
rs themselves, and also because of the specialised data centres, cooli
ng systems and power supplies that mainframes required. Personal compu
ters and industrial microcomputers are changing the situation dramatic
ally. The capital investment required to supply a programming staff wi
th personal computers is almost trivial. Software development in the f
uture can be carried out almost anywhere in the world. Software is a c
omparatively 'green' industry that is not harmful to the environment a
nd uses little in the way of natural resources. Many countries are now
entering the commercial software domain, and this trend should accele
rate in the 21st century. Software usage and consumption are also expa
nding rapidly on a global basis.