Real-time protection - AbsoluteAstronomy.com

Real-time protection, on-access scanning, background guard, resident shield, autoprotect, and other synonyms refer to the automatic protection provided by most antivirus

Antivirus software

Antivirus or anti-virus software is used to prevent, detect, and remove malware, including but not limited to computer viruses, computer worm, trojan horses, spyware and adware...

, antispyware, and other antimalware

Malware

Malware, short for malicious software, consists of programming that is designed to disrupt or deny operation, gather information that leads to loss of privacy or exploitation, or gain unauthorized access to system resources, or that otherwise exhibits abusive behavior...

programs, which is arguably their most important feature. This monitors computer systems for suspicious activity such as computer viruses, spyware

Spyware

Spyware is a type of malware that can be installed on computers, and which collects small pieces of information about users without their knowledge. The presence of spyware is typically hidden from the user, and can be difficult to detect. Typically, spyware is secretly installed on the user's...

, adware

Adware

Adware, or advertising-supported software, is any software package which automatically plays, displays, or downloads advertisements to a computer. These advertisements can be in the form of a pop-up. They may also be in the user interface of the software or on a screen presented to the user during...

, and other malicious objects in 'real-time', in other words while data is coming into the computer (for example when inserting a CD, opening an email, or browsing the web) or when a file already on the computer is opened or executed, in other words loaded into the computer's active memory.