The Difference Between Malware, Spyware, and Adware: Understand How Each Type Works, Effects, and How to Avoid Them

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Malware is a very general word for software that deliberately harms, restricts, alters, or stops your computer from working properly where the true purpose of the download or installation is hidden or difficult to find and not clearly explained to the user. The user does not give permission for installation and use. Malware includes adware, spyware, tracking cookies and infectors (worms, viruses, Trojans, backdoors, toolkits). The basic rule for safety is to use both updated anti-spyware and anti-virus software.

Malware can arrive through an internet download, as an email link or attachment, as a file sent between users of instant messaging, social networking communities, peer-to-peer file sharing programs, online games, online video games or chatrooms or a link to a malicious webpage. Sometimes when someone downloads a “free” program from the internet, whether the program is for access to a restricted website, to play a game, or to use a peer-to-peer file sharing program, there can be compensation for the privilege of downloading the free software. This compensation can be:

  • In the form of a phone bill from a long distance internet access connection.
  • Giving your permission by marking the box that says you already read the “Terms of the Agreement” or the “License Agreement” before downloading. These agreements can say you are giving your permission to the company or website to track or monitor your online activities or behavior for marketing or statistical purposes, or you can be giving your permission for this company or website to use the resources of your computer.

Indications of Malware

Indications that some kind of malware is probably installed on your computer can be:

  • The browser’s home page keeps changing
  • Pop-up advertisements appear when your browser is closed, pop-ups immediately begin when you connect to the internet or the amount of pop-up advertisements is way too much.
  • Strange icons appear on your desktop without your prompting or knowledge of the program
  • The computer light is blinking (meaning that your computer is processing information) at unusual or unexpected times. This is difficult to observe with broadband since there is not a visual difference between incoming and outgoing data.
  • Your browser settings keep changing, including the webpage you designate as your internet start-up page
  • Files are uploaded or downloaded without your prompting or permission


Adware displays advertisements directed to your individual preferences based on websites you visited online, individual buying choices and the configuration of your computer’s hardware and software. This is not different than looking at an article of clothing in a store and someone continually puts a competitor’s item in your view. Adware can track your online activities, collect your web surfing habits, email addresses, and purchase preferences. It can also gather information about the hardware and software installed on your home computer and sends that information to marketers.

Many times the internet user does not understand or read the usually lengthy and confusing EULA (End-User License Agreement) before agreeing to the terms because they want to immediately download the free game, screen saver, utility or advertisement supported software. The internet user can use the download with no monetary charge in exchange for viewing advertisements while online inside a webpage or as a pop-up window. Advertisers typically do not consider adware as malware because the internet user agrees to the EULA before copying, downloading, installing, registering or using the software. The computer user usually has an option to buy a license to stop the advertisements from displaying. The computer user knows that in exchange for not buying a license, they will see advertisements that the company hopes they will click on and buy the product or service. Other adware License Agreements include permissions from the user to the company for privileges stated in the agreement. The computer user should always read and understand any agreement before accepting. If you do not read and understand what you are agreeing to, you may be giving your permission to the company or third party to monitor your activities while online.

This monitoring can include where you go, where you shop or your web browsing preferences and habits. Companies find this information useful so they can generate advertisements customized specifically for your interests, likes, and dislikes. Adware is generating much discussion about balancing the responsibilities and rights of companies and the privacy of customers. So, be sure you read and understand all agreements before accepting them.


Spyware is tracking software that hides itself (runs in the background) and gathers information without the computer owner’s or user’s knowledge or permission for the benefit of someone else. It uses the computer owner’s internet connection without permission to send the collected information to whomever the tracking software designates. This is the reason every home computer should have an invalid default internet connection. Spyware can compromise the safety of your passwords, logon information, financial, or personal information. Information collected can include your online habits and preferences (where you go, where you shop, for what, how much, how often, etc), each key you press on your keyboard, passwords, logon information, account and financial information, online correspondence and conversations or whatever information is stated in the agreement.

What spyware and malware have in common is the ability to collect and distribute your personal information without your permission. Malware can also send and make computer resources and information available to unknown recipients or remote users without your knowledge or permission. Both spyware and malware are possible methods for identity theft since the computer owner or user does not know about or does not provide their permission for the installation and use of the hidden program or file.

Unauthorized software installation without the computer user’s or owner’s permission can include:

  • Programs designed to help steal personal user information to commit identity theft without the user or owner of the computer providing their permission to do so.
  • Botnets – an unlimited number of computers infected with a program designed to simultaneously attack another computer or network without the knowledge or permission of the owner of each infected computer.
  • Disabling security without the computer owner or user providing their permission
  • Endless loop pop-up advertisements or adware when the computer user or owner does not deliberately activate the software either through an installed program or through understanding an End-User License Agreement.
  • Denial of Service attacks
  • Modem Hijacking – the computer user can incur financial telecommunication charges without their prior permission
  • Changing browser settings without the computer owner’s or user’s permission
  • Evading uninstalls by deceptive or unfair means
  • Falsifying options for uninstallation
  • Installing personal and financial information collection features without the computer owner’s or user’s permission
  • Installing keystroke logging software on a computer used or owned by someone whom you are not responsible for their safety and conduct .

Guidelines to Avoid Spyware

Follow internet safety guidelines including:

  • Not opening emails or email attachments from unknown senders
  • Block or don’t click on suspicious pop-up windows
  • Don’t open files that are more prone to be associated with malware such as .bat, .com, .exe, .pif, .txt.vbs, .htm.exe or .vbs
  • Don’t download or execute applications from untrusted sources.
  • Avoid phishing scams.
  • Use updated anti-virus and anti-spyware software regularly.