From:What is Antivirus/Antispyware? Internet Security Vs Antivirus.
Designed to combat and eliminate threats while surfing the web and offline. Internet security combines all the protection tools under one roof. Internet security is a collective of tools that protect the computer against the common threats of surfing the web and offline, it is include: Antivirus (which protect against, Malware, Viruses, Trojans, Spyware, Worms, Bots), Scan Emails, Identity Protection, Firewall, Keep file information private, Conversation Encryptions, Parental Control, Antispam, Password Protection, Real-time notices, Antiroot kit, Antiphishing and more.
Internet security is recommended for all uses, since it is a complete protection package. There is a big selection of brand names such as: BitDefender, Norton, ESET, Avira, AVG and more.
Antivirus software is computer program that discover and remove harmful programs such as: Worms, Viruses, Malware, Worms, Bots, and Spyware. The program will search the hard drive for harmful programs and will disarm, or delete those programs. Majority of the antivirus software on the market offer an auto update, this feature will add the virus names and how to deal with them, so the antivirus will be able to detect any new harmful programs. The newer versions of the antivirus programs will be able to detect the viruses, by the way it operates that is called heuristic algorithm they will use it in conjunction with auto update.
Some companies such as AVG will offer an antivirus plus firewall, or other variation with antivirus, anther company to offer this is ESET NOD32 Antivirus 4 it offer antivirus and Antispyware. Not all antivirus on the market will offer that. As differ from Internet Security, Internet Security will contain this and more protection features.
Designed to combat or eliminate spyware on a computer system. Antispyware will protect your computer against the following: Security breach, pop-ups, slow performance that caused by harmful programs called spyware, usually most of the spyware programs can be found under free software downloaded from the internet.
Antispam will combat or eliminate spam on e-mail clients. Spam is a also called "Junk Mail" which most of it came in a form of advertisement, or unwanted e-mails, the software will be able to detect which mail is spam and which one is not, so the users could enjoy keeping getting only the materials that are relevant to them.