How might computers contribute to unemployment in modern society?
In the short term, computers can contribute to unemployment, but this effect should disappear in the long term.
The main way that computers can cause unemployment is if they make certain people's jobs unnecessary. For example, firms used to employ large numbers of stenographers and typists. Computers have made these people unnecessary.
Computers can also cause unemployment in certain countries. For example, the rise of the internet means, for example, that an American who specialized in typing up medical records could be replaced by a lower-cost individual in another country. The records could be transmitted by the internet.
Economic theory suggests that this is good in the long term. Computers will open up new job categories even as they close some jobs off. For an example of how this worked historically, think of the change from horses to cars. This put many people out of work (saddle makers, for instance) but opened up many new kinds of jobs.
The computer has eliminated jobs and created jobs, so it is difficult to know whether there has been a net gain or loss. Many people who used to have secretaries to do their typing now do their own word processing, for example, but more people are employed to teach novices how to use computers and to manage or repair them. Carriers such as FedEx, UPS, and the United States Postal Service have had a decrease in document delivery because of email, but websites like ebay and Amazon have generated an incredible demand for package delivery. Each new technological advance creates and eliminates jobs. Blacksmiths were put out of business by the automobile, but think of all the new jobs that industry created. There is always a period of adjustment with each new wave of technology, as people struggle to acquire new skills that will make them employable when their previous jobs are eliminated by technology, but many people do make successful adjustments.
If we as a society maintain the view that computers (and not us) are responsible for social changes, then we are using a deterministic view of technology which is not very productive. Instead, we should turn back to social theories which state that the individual and the use he or she gives to the technology is what is responsible for social change. This is what is called an "instrumentalist" view of technology. If we all adopt the instrumental versus the deterministic and reductionist mentality, we will see that, in the end, computers would not be any obstacle in the process of employment or job creation. In fact, they may be the tool that we all need to use malleably to enhance what we already have and expand our possibilities.