1 Stress echocardiogram: This is an echocardiogram that is performed while the person exercises on a treadmill or stationary bicycle. 2  This test can be used to visualize the motion of the heart's walls and pumping action when the heart is stressed.
Viruses require an active host program to cause damage and infect other executable files or documents, while worms are stand-alone malicious programs that can self-replicate and propagate via computer networks, without human help.
What is a computer virus and what is a web scripting virus? A computer virus is a computer program that can replicate itself and spread to multiple computers. It is used to refer to malware, including adware and spyware programs. Malware includes Trojan horses, rootkits, and computer worms. A web scripting virus is a type computer security vulnerability through websites that breaches your web browser security. This allowes the attackers to inject client-side scripting into the web page.