What is Adware?
Adware is the generic name for unwanted programs that fall under the category “malware”. Adware is most likely but not always built into free software you can download from the internet “freeware” or shareware programs: If you download a freeware program, the adware is most likely installed on your system without your knowledge or consent. Sometimes a Trojan horse secretly downloads an adware program from a website and installs it on your computer.
Internet browsers that are not up-to-date often contain vulnerabilities. Such browsers are vulnerable to malicious applications, usually called Browser hijackers that can download adware to your computer. Browser hijackers can change browser settings, redirect mistyped or incomplete URLs to a specific site, or change the default home page. Browser Hijackers can also refer search terms to paid (often deceptive) websites.
Adware programs are usually in no way visible in the system. They have not listed under Start | Programs, there are no icons in the system bar, and there is nothing in the task list. There is seldom the possibility of uninstalling and attempting to remove adware manually can cause the program in which the adware came to malfunction.
What is Spyware?
Adware is similar to “spyware” in many aspects and often works together, the adware manages the advertising redirects and responds to the data obtained by the spyware.
As the name suggests, spyware is software that is designed to trace your data and forward it to cybercriminals or suspicious advertisement networks without your knowledge or consent. Such programs can, among other places, record your keystrokes (‘keyloggers’), Collect confidential data (passwords, credit card numbers, pins, etc.), retrieve email addresses or follow surfing habits. Besides all this, spyware inevitably also affects the performance of your computer.