Malware refers to any software that is designed to disrupt the operations of your computer. It could cause many negative effects such as depriving you of access to information, leaking sensitive information to a third party, or causing your device to be unusable in its entirety.
Malware removal is the process that scans your device to detect any malware and eliminate anyone that is found. There are specific software programs built for this process, and they make use of various processes to detect malware. Most software look for malware by checking for the signature of a known malware program on your device; the companies behind these tools have large databases of these signatures that their software runs checks against. The malware removal program scans all files on your device to detect the presence of any known signatures.
Lately, malware removal programs are also employing artificial intelligence and machine learning to fish out malware, especially the type that may get past the usual process.