A virus is a program that is capable of replicating with little or no user intervention, and the replicated software also replicate further. Viruses can piggyback on real software programs or that can be transmitted by themselves. For example, a virus may attach itself to a program such as a spreadsheet program, an email or an image. Antivirus software is the most basic internet security software that an internet user should have to protect against the tens of thousands of viruses.

Adware is software that is generally downloaded onto your computer with or without your permission and generates popup advertising and can slow down your computer. Spyware is the more malicious of the two and can generate ads but also can transmit your personal data back to a third party. Adware and spyware removal software stops both of these issues and eliminates unwanted advertising and protects you from having personal data stolen.

Firewall is a software application used to protect a single Internet-connected computer from intruders. Personal firewall protection is especially useful for users with "always-on" connections such as DSL or cable modem. Such connections use a static IP address that makes them especially vulnerable to potential hackers. Often compared to anti-virus applications, personal firewalls work in the background at the device (link layer) level to protect the integrity of the system from malicious computer code by controlling Internet security connections to and from a user's computer, filtering inbound and outbound traffic, and alerting the user to attempted intrusions.

Spam is e-mail that is both unsolicited by the recipient and sent in substantively identical form to many recipients. Thus, a common synonym for spam is unsolicited bulk e-mail. Some definitions of spam specifically include the aspects of email that is unsolicited and sent in bulk. Spam filter is a program that is used to detect unsolicited and unwanted email and prevent those messages from getting to a user's inbox. Like other types of filtering programs, a spam filter looks for certain criteria on which it bases judgments.

Parental Control Software: A special browser or filtering program designed to reject Web sites not suited for children. Such software may screen pages by word content, site rating or by URL, using an updated database of objectionable sites, or any combination of these techniques.

Rootkit is a set of software tools intended to conceal running processes, files or system data from the operating system. Rootkits have their origin in relatively benign applications, but in recent years have been used increasingly by malware to help intruders maintain access to systems while avoiding detection.

Popup Blocker: There are two distinct typeds of popups. Browser based popups - when you are visiting a website and the website generates a popup. Adware based popups - when you are not "moving around" the internet and just start getting popups. Both tend to be annoying but may not be dangerous.

Privacy software protects your privacy by removing your Internet records and other temporary internet files from your computer. Deleting your browser cache and history will not protect you! All other records from Internet stay on your computer unsafe! Anyone who uses your computer can see what internet websites you've visited. Privacy software deletes all your temporary html pages, which was downloaded from Internet, pictures and URL history records.