connected to the device as memory units but are capable of recording each stroke made on the keyboard. Some spyware authors infect a system through security holes in the Web browser or in other software. When the user navigates to a Web page controlled by the spyware author, the page contains code which attacks the browser and forces the download and installation of spyware. The installation of spyware frequently involves Internet Explorer. Its popularity and history of security issues have made it a frequent target. Its deep integration with the Windows environment make it susceptible to attack into the Windows operating system. Internet Explorer also serves as a point of attachment for spyware in the form of Browser Helper Objects, which modify the browser's behaviour. Effects and behaviors A spyware rarely operates alone on a computer; an affected machine usually has multiple infections. Users frequently notice unwanted behavior and degradation of system performance. A spyware infestation can create significant unwanted CPU activity, disk usage, and network traffic. Stability issues, such as applications freezing, failure to boot, and system-wide crashes are also common. Usually, this effect is intentional, but may be caused from the malware simply requiring large amounts of computing power, disk space, or network usage. Spyware, which interferes with networking software commonly causes difficulty connecting to the Internet. In some infections, the spyware is not even evident. Users assume in those situations that the performance issues relate to faulty hardware, Windows installation problems, or another malware infection. Some owners of badly infected systems resort to contacting technical support experts, or even buying a new computer because the existing system "has become too slow". Badly infected systems may require a clean reinstallation of all their software in order to return to full functionality. Moreover, some types of spyware disable software firewalls and antivirus software, and/or reduce browser security settings, which opens the system to further opportunistic infections. Some spyware disables or even removes competing spyware programs, on the grounds that more spyware-related annoyances increase the likelihood that users will take action to remove the programs. Keyloggers are sometimes part of malware packages downloaded onto computers without the owners' knowledge. Some keylogger software is freely available on the internet, while others are commercial or private applications. Most keyloggers allow not only keyboard keystrokes to be captured, they also are often capable of collecting screen captures from the computer. A typical Windows