A: Malware is any kind of software that compromises security on a user's computer. Malware includes spyware, viruses, trojan horses, and a host of other sometimes whimsical names for security compromising software.
A: Phishing is a social engineering technique whereby hackers send authentic-looking emails to a user in order to persuade the user to share some sort of valuable information (e.g., for identity theft or other fraud). One specialized technique is 'spear phishing'. In this scam, email apparently from a trusted organizational representative is sent to that person's organization in order to glean credentials for subsequent hacking attacks.
A: Spyware is computer software that is generally surreptitiously installed on a computer in order to collect information from the computer's user. Such information includes:
Note that spyware is installed without a users' permission. Some programs (e.g., filtering software for juveniles) are installed by parents or institutions for the express purpose of 'spying'.
A: A firewall is a piece of hardware (or sometimes software on a user's computer) that examines all network traffic destined to one or more computers. It applies filtering rules to try to remove malicious traffic before it can reach a user's computer.
A: Antispyware software tries to find and disable (and/or remove) spyware from your computer. Historically, spyware came as a sort of "add on" to other malware that inundated a computer's user with pop-up advertising.
A: Antivirus programs monitor a computer's file creation mechanism and use sophisticated pattern-matching mechanisms to see if new files have a 'signature' that matches any known malware.
A: Passwords are the weakest link in any security situation. The temptation to lend a workstation or account to someone is very high. Keeping your passwords secret is the first step to keeping your system secure.