Computing Issues That Affect Us All Computer Crime

Our legal system is gradually developing a legal framework for working with computers and working on the Internet. The most prevalent breach of law in cyberspace is software piracy, or the illegal copying or use of a program. Several types of copy protection schemes can be used to stop or slow down pirates.

Computer Viruses

A computer virus is a parasitic program that can replicate itself, infect computers, and destroy data. Viruses are most commonly spread by infected disks and when users download infected files over a network or from the Internet. A new breed of e-mail viruses is spread via files attached to e-mail messages or in the body of an e-mail message. Users can protect their data and software by using an antivirus program and by keeping the program's virus definitions up to date.

Theft

Computer-related theft is a costly problem for organizations and individual users, especially those who use portable computers. Many companies literally lock their computer systems with anti-theft devices. Software theft is a common problem in organizations where software is left unattended. Companies can combat the problem by keeping software in a locked storage location and overseeing its installation on individual computers. Data theft is perhaps the greatest concern to organizations. Hackers steal data by accessing a computer's disks over a network. In addition to stealing data, hackers have been known to destroy data, crash computer networks, and steal funds electronically. Organizations can protect the data on their networks by taking appropriate security measures. Basic measures include requiring users to provide identification and passwords before accessing the network. More sophisticated measures include encrypting data to make it unusable to anyone without the proper decoding key.

Computers and the Environment

The computer industry has become known for planned obsolescence, with both hardware and software being replaced or upgraded every couple of years. When disposed of improperly, obsolete hardware and software contribute to pollution and negatively affect the environment. Many newer devices are designed under the Energy Star program, which sets power-consumption standards for computer equipment.

Ethical Issues in Computing

Widespread access to computer technologies has created many ethical dilemmas. Government, legal, and computing professionals continue to debate computer-related ethical questions and attempt to develop laws that protect the freedoms of computer users while limiting immoral or illegal use of computers.

Unit 2. Input, Output, Storage Devices

Standard Methods of Input

The Keyboard

A standard computer keyboard has about 100 keys; each key sends a different signal to the CPU. Most keyboards follow a similar layout, with their keys arranged in five groups. Those groups include the alphanumeric keys, numeric keypad, function keys, modifier keys, and cursor-movement keys. Most keyboards use the QWERTY layout, which gets its name from the first six keys in the top row of letters. Several ergonomically correct keyboards are available to help users prevent hand and wrist injuries. When you press a key, the keyboard controller notes that a key was pressed and places a code in the keyboard buffer to indicate which key was pressed. The keyboard sends the computer an interrupt request, which tells the CPU to accept the keystroke.