Much of today’s malware (short for malicious software), which
includes Trojans, backdoors and spammers’ proxy servers as well as
viruses and worms, is purpose-built to hijack users’ machines; and
a single Trojan can easily be found on many thousands of infected
PCs. Malicious code may be embedded in e-mail, injected into fake
software packs, or placed on ‘grey-zone’ web pages for download by
a Trojan installed on an infected machine. There has also been a
growth in spyware,adware, dialers and other ‘unwanted’, but
non-viral, programs.
