The goal of intrusion detection systems is that of a dynamic backup to static corporate defenses. Companies are attracted by the lure of the Internet, but increased connectivity implies increased risk to such company data as financial records, strategic plans, trade secrets, inventions, customer lists and source code. Corporations are also concerned about legal liability resulting from hackers who bounce attacks through exploited systems.
Individuals are as much at risk as corporations.
This risk can be to financial information, such as credit card numbers, passwords to pay online services or account information for online financial institutions. For example, if a hacker breaks into your home system and steals the keys to your online stock portfolio, they may be able to trade away your life's savings, and you will probably not be able to receive compensation for your losses. Intruders may also be able to view private information such as web-surfing history, medical records, love letters, wills and image collections. There is no such thing as secure system. Even cutting cables and turning off a machine doesn't prevent intrusions.