1. Internet Security Software (aka Antivirus Software)

2. Internet Security Software (aka Antivirus Software)
What is Malware? Types of Malware
Paid-for vs Free antivirus programs
Do I need a separate Antivirus program? Is my integrated Windows or Mac security enough?
Paid-for vs Free and Windows vs Mac - An alternative view
Malwarebytes
PC Mag UK: Anti-virus reviews
Tom’s guide: Anti-virus reviews
Which? Anti-virus reviews

3. What is Malware? Types of Malware

4. What is Malware?
Malware is short for malicious software, meaning software that can be used to:
compromise computer functions,
steal data,
bypass access controls, or
otherwise cause harm to the host computer.
Malware is a broad term that refers to a variety of malicious programs.
All information in this section is taken from:
Further information at:
What is Malware? at
Types of Malware at
Different Kinds of Malware Terms Explained at
Types of Malware at
Know the Different Types of Malware at

5. Adware
Adware (advertising-supported software) is a type of malware that automatically delivers advertisements.
Common examples of adware include pop-up ads on websites and advertisements that are displayed by software.
Often times software and applications offer “free” versions that come bundled with adware. Most adware is sponsored or authored by advertisers and serves as a revenue generating tool.
While some adware is solely designed to deliver advertisements, it is not uncommon for adware to come bundled with spyware (see below) that is capable of tracking user activity and stealing information.
Due to the added capabilities of spyware, adware/spyware bundles are significantly more dangerous than adware on its own.

6. Bot
Bots are software programs created to automatically perform specific operations.
While some bots are created for relatively harmless purposes (video gaming, internet auctions, online contests, etc), it is becoming increasingly common to see bots being used maliciously.
Bots can be used:
in botnets (collections of computers to be controlled by third parties) for DDoS (Distributed Denial of Service) attacks;
as spambots that render advertisements on websites;
as web spiders that scrape server data; and
for distributing malware disguised as popular search items on download sites.
Websites can guard against bots with CAPTCHA* tests that verify users as human. (*a backronym for "Completely Automated Public Turing test to tell Computers and Humans Apart")

7. Bug
In the context of software, a bug is a flaw produces an undesired outcome. These flaws are usually the result of human error and typically exist in the source code or compilers of a program.
Minor bugs only slightly affect a program’s behaviour and as a result can go for long periods of time before being discovered.
More significant bugs can cause crashing or freezing.
Security bugs are the most severe type of bugs and can allow attackers to bypass user authentication, override access privileges, or steal data.
Bugs can be prevented with developer education, quality control, and code analysis tools.

8. Ransomware
Ransomware is a form of malware that essentially holds a computer system captive while demanding a ransom.
The malware restricts user access to the computer either by encrypting files on the hard drive or locking down the system and displaying messages that are intended to force the user to pay the malware creator to remove the restrictions and regain access to their computer.
Ransomware typically spreads like a normal computer worm (see below) ending up on a computer via a downloaded file or through some other vulnerability in a network service.

9. Rootkit
A rootkit is a type of malicious software designed to remotely access or control a computer without being detected by users or security programs.
Once a rootkit has been installed, it is possible for the malicious party behind the rootkit to remotely execute files, access/steal information, modify system configurations, alter software (especially any security software that could detect the rootkit), install concealed malware, or control the computer as part of a botnet.
Rootkit prevention, detection, and removal can be difficult due to their stealthy operation.
Because a rootkit continually hides its presence, typical security products are not effective in detecting and removing rootkits. As a result, rootkit detection relies on manual methods such as monitoring computer behaviour for irregular activity, signature scanning, and storage dump analysis.
Organizations and users can protect themselves from rootkits by regularly patching vulnerabilities in software, applications, and operating systems, updating virus definitions, avoiding suspicious downloads, and performing static analysis scans.

10. Spyware
Spyware is a type of malware that functions by spying on user activity without their knowledge.
These spying capabilities can include:
activity monitoring,
collecting keystrokes,
data harvesting (account information, logins, financial data),
and more.
Spyware often has additional capabilities as well, ranging from modifying security settings of software or browsers to interfering with network connections.
Spyware spreads by:
exploiting software vulnerabilities,
bundling itself with legitimate software, or
in Trojans.

11. Trojan Horse
A Trojan horse, commonly known as a “Trojan,” is a type of malware that disguises itself as a normal file or program to trick users into downloading and installing malware.
A Trojan can give a malicious party remote access to an infected computer.
Once an attacker has access to an infected computer, it is possible for the attacker to:
steal data (logins, financial data, even electronic money);
install more malware,
modify files,
monitor user activity (screen watching, keylogging, etc),
use the computer in botnets, and
anonymize internet activity by the attacker.

12. Virus
A virus is a form of malware that is capable of copying itself and spreading to other computers.
Viruses often spread to other computers by attaching themselves to various programs and executing code when a user launches one of those infected programs.
Viruses can also spread through script files, documents, and cross-site scripting vulnerabilities in web apps.
Viruses can be used to:
steal information,
harm host computers and networks,
create botnets,
steal money,
render advertisements,
and more.

13. Worm Computer worms are among the most common types of malware.
They spread over computer networks by exploiting operating system vulnerabilities.
Worms typically cause harm to their host networks by consuming bandwidth and overloading web servers.
Computer worms can also contain “payloads” that damage host computers. Payloads are pieces of code written to perform actions on affected computers beyond simply spreading the worm.
Payloads are commonly designed to steal data, delete files, or create botnets.
Computer worms can be classified as a type of computer virus, but there are several characteristics that distinguish computer worms from regular viruses.
A major difference is that computer worms have the ability to self-replicate and spread independently while viruses rely on human activity to spread (running a program, opening a file, etc).
Worms often spread by sending mass s with infected attachments to users’ contacts.

14. Spam Spam is the electronic sending of mass unsolicited messages.
The most common medium for spam is , but it is not uncommon for spammers to use instant messages, texting, blogs, web forums, search engines, and social media.
While spam is not actually a type of malware, it is very common for malware to spread through spamming. This happens when computers that are infected with viruses, worms, or other malware are used to distribute spam messages containing more malware.
Users can prevent getting spammed by avoiding unfamiliar s and keeping their addresses as private as possible.

15. Paid-for vs Free antivirus programs

16. Paid-for antivirus software - 1
A paid-for security suite will usually include antivirus software, protection against scams, and a firewall.
Depending on the number of devices to be protected, the typical cost is £20 - £70 per year.
Paid-for security software suites often come with extra features, such as:
parental controls; and
tools for maintenance, back-up and recovery to help restore the computer in the event of a disaster.
If there's a particular feature or function you want, make sure the program you download has it.
Generally, paid-for packages have better customer service & technical support than free ones.
Most have options for multiple licences (for two or more computers) at reduced cost. Some also have reductions for buying a licence for two or more years.
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17. Paid-for antivirus software - 2
Pros:
Provides an all-round security solution accessed through a single interface.
Individual components are automatically updated at the same time so you get protection against the latest threats.
Cons:
They can be expensive and you’ll also face ongoing costs, usually in the form of an annual subscription, to receive updates after the initial period of protection is over (usually a year).
Some security suites can place a drain on system resources, too, potentially slowing down your computer.
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18. Free antivirus software - 1
Depending on the type of computer you have, it may already come with certain security features installed on it.
Windows 8.1 and Windows 10 PCs come equipped with Windows Defender – see more below.
Apple Macs have a better reputation for security than Windows PCs, and include a built-in firewall to block attacks from malicious users online – also see more below.
You can download free antivirus tools from the internet that provide a good level of protection.
It’s possible to get most of the features that are included in paid-for internet security by using a combination of free antivirus downloads, although they won’t be packaged up neatly in one place, and you can risk compatibility problems.
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19. Free antivirus software - 2
Pros:
You can use your chosen antivirus, anti-spyware, anti-spam and firewall programs in tandem to completely protect your PC or Mac without spending a penny.
Because they’re free, you can try out different packages before settling on the one for you.
Cons:
They provide only a basic level of protection and lack the extra features of paid-for security software.
You’ll have to keep each individual program updated to ensure you’re protected against the latest threats.
Free antivirus software is typically for use on a single computer, so you’ll need to download, install and manage a separate version if you have more than one computer.
Would you trust the security of your home to a free lock or free locksmith? (TD)
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20. Do I need a separate Antivirus program
Do I need a separate Antivirus program? Is my integrated Windows or Mac security enough?

21. Windows 8 & Windows 10 security
Which? found Windows 8 & Windows 10 to be adequately secure in their tests.
Windows Defender includes antivirus protection along with anti-spyware features. It runs in the background and notifies you when you need to take action. It includes:
a two-way firewall that monitors the information going back and forth to the internet;
a SmartScreen filter to help protect against phishing scams;
parental controls to monitor children’s activities online;
a Secure Boot option that prevents malware from gaining a foothold on your PC during start-up.
Pros: Windows 8 & 10 have strong built-in security and antivirus features.
Cons: Because of the sheer amount of Windows users, Microsoft’s operating system is frequently made the target of hackers and virus creators. If Windows Defender is your only line of defence, Which? recommends upgrading to a standalone security program.
PC users with Windows versions prior to Windows 8 should certainly install separate security software – nowadays, Microsoft Security Essentials just isn't watertight enough.
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22. Mac security software
Despite a better reputation for security than Windows PCs, Apple Macs are not immune from viruses and malware. With more Apple products being sold, the target audience for hackers becomes more attractive, thus making it more likely that viruses will be designed specifically to attack Macs, so it makes sense to think about Mac security software.
In fact, Which? has seen a recent increase in Mac malware, typically in the form of annoying pop-up adverts and software that makes unwanted changes to settings, or causes other programs to malfunction.
Apple continues to boost security in each new version of the MacOS operating system. But Macs do not include antivirus or anti-spyware software, although they do have a built- in firewall to block attacks from malicious users online. There’s plenty of paid-for and free security software for the Mac to choose from.
Pros: Apple computers are generally less vulnerable than PCs, so you may decide that you don’t need to splash out on antivirus software for your Mac.
Cons: Perhaps due to Apple computers' reputation for being less susceptible to malware, there aren’t a huge amount of security packages available – and those we have tested scored worse, on average, than antivirus suites for Windows.
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23. Paid-for vs Free Windows vs Mac An alternative view

24. An alternative view
Many Windows users believe they don't need to pay for antivirus software.
Most Mac and Android users think they don't need protection at all.
It's true that Windows' much higher profile makes it the biggest target, but OS X and Android are just as vulnerable to malware.
It's worth paying for Windows antivirus software, because even the best free software leaves out features tomsguide considers essential. (Many antivirus products are sold online for much less than their list prices.)
Mac and Android users have other options:
the Mac AV product recommended by tomsguide costs nothing, and
most Android security apps have free versions.
Source:

25. Malwarebytes

26. Malwarebytes - 1
Malwarebytes is not a traditional antivirus protection program, and the company says it isn't directly competing with regular antivirus software products.
It does not sit in the background and monitor computer activity: it is intended to complement existing anti-virus solutions without causing conflicts that can arise from using two anti-virus products at the same time.
Malwarebytes is an application that is run periodically or on demand, in order to scan files, determine if anything is amiss, and then provide the proper fix to ensure system security.
Users shouldn't rely on Malwarebytes Anti-Malware Free as their only security program. It's meant to complement regular antivirus software, but that doesn't mean they should overlook it.
Free & ‘Premium’ versions of the product are available: the free version does not let users schedule scans, so you'll have to manually open the program and click the Scan button each time you want to check for malware.

27. Malwarebytes - 2
“Malwarebytes Anti-Malware Free is not antivirus software. It can't protect a PC from infection, but it does an excellent job of cleaning out malware that's already on your system — and doesn't interfere with any antivirus software that's already installed. We especially like the Chameleon feature, which disguises Malwarebytes so malicious programs can't find it. We recommend Malwarebytes Anti-Malware Free as a complement to any antivirus program.”
Source: See also:

28. Malwarebytes - 3 Some advisors suggest that the use of:
Windows Defender,
supplemented by periodic use of
Malwarebytes
constitutes adequate protection for a system.
Whether that is the case depends largely on the amount and type of your computer usage.
In any event, you need to remember to run Malwarebytes manually, and at least weekly.

29. PC Mag UK Anti-virus reviews
These reviews all date from Sep. & Oct 2016

30. Best Antivirus Protection of 2016 (PC Mag)
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31. Best Security Suites of 2016 (PC Mag)
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32. Tom’s Guide Anti-virus reviews
These reviews all date from Sep. 2016

33. Summary of Best Antivirus Software & Apps 2016 (Tom’s Guide)
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34. Best Basic PC Antivirus Software 2016 (Tom’s Guide)
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35. Best Midrange PC Antivirus Software 2016 (Tom’s Guide)
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36. Best Free PC Antivirus Software 2016 (Tom’s Guide)
Note ranking of Windows Defender
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37. Best Mac Antivirus Software 2016 (Tom’s Guide)
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38. Best Android Antivirus Apps 2016 (Tom’s Guide)
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39. Which? Anti-virus reviews
Note: These reviews all date from Nov./Dec. 2015

40. Windows + Free (No ‘Best Buys’) (Which?)
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41. Windows + Paid-for + ‘Best Buy’ (Which?) Page 1
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42. Windows + Paid-for + ‘Best Buy’ (Which?) Page 2
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43. Mac + Free + ‘Best Buy’ (Which?)
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44. Mac + Paid-for + ‘Best Buy’ (Which?)
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