Computer Science Illuminated, 7th Edition

17.3 Malicious Code

We’ll now explore deliberate attempts to gain inappropriate access or cause other problems using software. Malicious code, or malware, can be defined as any program code that explicitly attempts to bypass appropriate authorization safeguards and/or perform unauthorized functions. Such code is transferred to a computer across a network or from removable media such as USB memory sticks. Malicious code may cause serious damage, such as the destruction of data, or it may merely create a nuisance, such as popping up unwanted messages.

There are many categories of malicious code. The term computer virus is often used to describe any malicious code, although it’s really just one type of problem. A virus is a program that embeds ...