ISSUES IN COMPUTING
Because faults can develop in computer systems, it is important to keep copies of valuable data using a backup system. This is especially important in a network where many users are storing vast amounts of data. Networks also require security systems to control access. Login names and passwords are often used, but these may be combined with the use of plastic swipe cards containing a user identification number. Some computer systems use recognition systems that scan and identify characteristics of the user such as their fingerprints, facial features, voice, or eyes. Computer crimes include: 1. hacking – unauthorized access to computer systems and tampering with other users’ data. 2. pirating, i.e. illegally copying and selling programs. 3. intentionally attempting to spread viruses. Viruses are programs that have been written to make a computer behave in an unexpected and undesired way. Although they are often relatively harmless, they sometimes cause a lot of damage. They are usually designed to remain hidden and dormant until a particular time, or until the user performs a particular action, such as pressing a particular combination of keys. They can replicate themselves, and often attach themselves to other programs. It is common for a user to have a virus program on their disk without being aware of it. Viruses can be found and removed by anti-virus programs, which scan disks and files looking for programming code that is known to belong to particular virus programs. When a piece of virus code is found, the virus can be identified, and an appropriate program run to delete the virus code from the disk or file. Plane text email messages cannot contain a virus, but viruses can be carried in email attachments, i.e. files attached to email messages. Some viruses are much more common than others and are often unknowingly downloaded from a network system such as the Internet. Care should be taken to check for viruses when using removable disks or when transferring files. 3 Answer the following questions: 1I s it important to keep copies of valuable data using a backup system? Why? 2 Do networks require security systems to control access? 3 What computer crimes do you know? 4 What are viruses written for? 5What is the principle of operation ofanti-virus programs? 6 Can plane text email message contain a virus?
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