What is Adware? Adware Definition & Examples

How to recognize adware, resist it and prevent annoying programs from flooding your PC? We research different types of adware to counter them effectively.

You may be interested in taking a look at our other antivirus tools:
Trojan Killer, Trojan Scanner.

Adware - What Is It & How To Remove It? Keep Your Privacy Well | Gridinsoft

What is Adware?

GRIDINSOFT TEAM
Oh, why do this ad appear again and again? And there are even more of them! Blinking, with the absurd contents and 100% fake offers, they fill your browser so hard that you see it even on the home page. Which sort of curse does so?

Adware is, literally, advertising software. That sort of program is created to show you the advertisements forcibly. To do so, viruses make several changes to your system - primarily in the web browsers and networking settings.

Networking in Windows is partially controlled by the HOSTS file. That file is kept in the system partition and contains the information about DNS servers it must connect to the server you need. Usually, all pages used by adware to show you the ads are shielded from the inside to prevent those pages from being banned by a web browser. When you get your HOSTS file edited, your PC connects to one DNS address of the adware’s server, which is not blocked for the connections.

Browser settings are changed for several reasons. First, viruses can change your homepage to fit several advertisements. Another possible change is the blockage of your settings window. It is especially relevant when adware is spread as a browser plugin. This action is done to prevent the web browser reset - an ultimate way to eliminate unwanted browser plugins.

How does an adware work

Adware works by quietly installing itself onto your PC, hoping you’ll – accidentally or not – click on an advert it displays. This is because, after all, adware exists to make money (but not for you). Adware creators and distributing vendors make money from third parties via either:


Pay-per-click (PPC)Adware developers get paid each time you open ads.
Pay-per-view (PPV)They get paid each time ads are shown to you.
Pay-per-install (PPI)They get paid each time bundled software is installed on a computer.

Adware can also track your search and browsing history to display ads that are more relevant to you. Once the adware developer has your location and browser history, they can make an additional profit by selling your information to third parties.

Developers who manage adware make their money like any other advertisers. There are two main differences between adware distributors and legit promoters: the people who order these ads and how those banners are paid. Usually, promoters are paid for each click on their advertisement. Meanwhile, fraudsters take contracts for pay-per-view ads. The price for each visitor is minimal, but when you show it forcibly to a massive number of victims - there is nothing complicated to earning thousands of dollars.

Adware mechanism

The difference in a character is much easier to understand. Will the legit company advertise itself with unlegit marketing tricks? Likely no. Hence, all ads adware forces you to see contain malicious content. Usually, those contents are links that redirect you to the unknown and likely unwanted site. In some cases, the downloading may start after clicking those ads. And only fraudsters know what the program is downloading. You may get coin miner, another adware, browser hijacker, or so. Regardless of the exact type of malware, it always is an unwanted consequence.

How can I get adware?

It is one of the most widespread types of malware. You can get it in about a dozen ways. Adware is spread through the malvertising, as a browser plugin, as a part of the “useful utility” you have just installed. You may discover that your system is infected even after using some seeding applications, like uTorrent. Every day, fraudsters discover more unobvious ways to get into your computer. And there is no reason for you to feel guilty - almost everyone sometimes needs to use questionable programs. And adware is not so dangerous if you remove it in time.

How bad adware can be?

Adware is not very dangerous itself. It makes too small changes to your system to make it malfunction exactly after the virus injection. However, if you remove it inappropriately and will not fix those changes, you will likely spectate various bugs in your web browser. Some problems may also appear in various apps with web-interface because of the modified networking settings.

Much more problems may be dealt with by the advertisements adware shows. As you read earlier, no legit companies will agree to an advertising contract with adware distributors. Hence, each ad can contain something malicious, and you never know which one and how dangerous this “something” is. Potentially unwanted programs, together with browser hijackers, will not make your files encrypted, like ransomware, for example, but it will bring chaos to your PC. Meanwhile, the trojan-miner activity will make your system impossible to use and may even lead to hardware failures.

Symptoms of Adware

Since the essence of adware is to throw advertisement banners at you, your device's infection with the disputed pest will not pass unnoticed. Such a penetration into your system would be the black advertisers' complete failure if you didn't notice the adware's presence at all. Here we list the recognizable signs of your device having adware and requiring a quick remedy.

  • Changed homepage. One of the first signs that something is wrong is that your web browser's homepage changes without any notification. Moreover, the page set instead is some suspiciously-looking advertising site you've never seen before. Most likely, your attempts to bring your previous homepage will be failing.
  • Changed search engine. Your browser's settings allow you to choose a default search engine. The browser will use it when you input your query into the address bar. Adware is often responsible for automatic and unauthorized changes to your browser's default search engine and alteration of search results (by advertising insertion, of course).
  • The unusual look of your web browser. Adware often comes as an add-on for your browser, a browser hijacker, or in the form of a rogue browser - a completely different program automatically assigned as your default browser. So, the emergence of a browser toolbar, let alone another browser you don't remember to install, is the clearest sign of adware infection.
  • Banners and pop-up windows. Advertisement banners thrown at you from the screen are the most common adware payload. The ads differ in the level of annoyance. Some appear to the left and right on the viewed webpage, which only decreases your device's performance, while others can flagrantly obstruct the visibility of the webpage you are trying to view. Besides, some ads are tied to your browser and only appear within it, while some kinds of adware can generate pop-up windows with links to the advertising pages without the browser even running.
  • Hypertext links where they're not supposed to be. This adware technique is one of the trickiest and, therefore - the most dangerous. Should it be accompanied by a standard banner shower, the victim will detect the infection before the grave consequences. But if the adware-generated hypertext links appear alone, it is hard to tell them from the links inherent to websites.
  • Decrease in device performance. It includes a CPU running speed decrease and a slower Internet connection speed. Adware-inflicted deceleration may range from minor freezings to program crashes. The worse the overall performance of your device is, the higher the probability of adware being fitted with or working alongside spyware or other covert malware.

How to avoid adware and remove it

Not all adware is malware. Some of it is packaged with legitimate software, and many new computers come with various adware installed. If you get a new PC, you can check the list of installed programs in the settings to see if any unwanted software accompanies the computer.

If your PC is new, another strategy is to reset it to a fresh install of Windows. By resetting the computer to factory conditions, it can remove all third-party apps, including any installed adware.

If you acquire adware on an existing computer, you can manually uninstall it using "Add or Remove Programs" in "Settings", but only if you can definitively identify which program on your PC is the cause of the spyware. If you can't, then you might want to install our anti-malware. This antivirus tool is adept at identifying and removing adware & spyware.

The best approach, of course, is prevention — avoiding getting infected with spyware, to begin with. So here are some easy steps you can take to avoid getting spyware on your PC:

  • Keep your computer up to date with the latest Windows updates.
  • Use anti-malware software. You should be sure your computer is protected by anti-malware or antivirus software, even if that's just the security tool built into Windows 10 or Windows 11. Our anti-malware software will be more effective at ferreting out adware, though.
  • Never click anything you don't fully trust. That includes both links and file attachments in email. That's also true about links and file downloads on websites of questionable quality.
  • Avoid installing free software from questionable sources. You can find many free utilities online that generate revenue using telemetrics, which is sometimes disclosed on the web page or in the license agreement when you install it.

Frequently Asked Questions

Is adware always tied to your web browser?
Actually, no! Modern adware most often is, but there is a type of malware, initially called 'adware,' that has no binding to browsers or any other visible applications. It shows as a process in Task Manager, initiated by some hard-to-detect executable, but you will not see it in the list of running apps. The effects of such a program, running in the background, are common for adware: pop-up windows, panels, banners, etc. Moreover, other programs, besides browsers, can be classified as adware regardless of whether they are malicious.
Is adware strictly speaking malware?
Definitely, there are programs that are called adware, but they have nothing to do with malware at all. These are countless benign applications that are adware in terms of their payback method: these programs are free, but they render ads for developers to profit. That is totally legit. As for adware that is overtly unwanted, experts disagree regarding its classification. Some specialists call such adware PUA, Potentially Unwanted Applications, explaining that if a program does not do open harm (financial, informational, reputational, etc.), it cannot be called malware. Their opponents note that adware behaves malevolently, neglecting users' convenience and wishes. 'Harm' is a term with a broad concept scope, after all.
How to remove adware without an antivirus? Is it safe?
You can remove the adware yourself in many cases. To do it, go to Windows' Programs and Features (you can type this section name right into the search bar,) choose the adware program from the list, and press Uninstall. If you are dealing with a browser plug-in, you can remove it in your browser's settings. The path varies throughout browsers, but it is roughly such: Main Menu -Settings - Extensions. Select the troublesome extension and press Remove. However, the pest often takes self-preservation measures. It can freeze the browser as you open its settings so that you don't delete an annoying extension easily. Moreover, if adware comes as a stand-alone program, it may not always be clear about its title. So you have to be sure which program exactly you wish to delete. Finally, you might run onto sneaky adware. In such a case, you will need to detect a foreign process, remove an executable file responsible for it, and you will also have to check for an automatic downloader that might still be present on your machine. The latter will download the adware again, no matter how many times you wipe it out. For such cases, an antivirus program is the best solution. As for the safety of such procedures, the only harm you can do is accidentally remove a benign program. Also, some downloaded applications may cease working after you delete their adware component.
Can there be adware undetectable to antiviruses?
Theoretically, it is possible. No antivirus can recognize every single malicious program. Security software only detects objects included in its algorithms - and nothing more. Solutions featuring neural networks and heuristic engines are not an exclusion, for they also work following certain settings. And if hackers detour those settings, they can potentially create undetectable malware. It can be adware, ransomware, whatever. The good news is that it is unlikely that someone would get busy creating such an elusive example of adware. The existing adware is constantly installed and removed by thousands of users, and the agencies that spread it still get their reward.
My browser is infected with adware, but I cannot access its settings! What should I do?
GridinSoft Anti-Malware has a Reset Browser Settings function for such cases. To perform it, click the Tools menu tab and select the Reset Browser Settings option. Choose browsers you want to reset and items that need to be back to default mode. Click Reset. That's all! You might want to reinstall the good browser extensions, but at least you won't be suffering from an unwanted program.