The act where an advertiser is made to lose his money by clicking on pay per click ads is called Click Fraud. Fraudsters do it basically to make the advertiser lose money. Moreover, it is done to help search engines earn more and also to reduce competition.
How to prevent a Click Fraud?
There a number of effective tools that can be used to prevent click fraud. Some of them are listed below:

• Who’s Clicking Who: This is a research tool which identifies Click Fraud by the use of keywords used, IP address and numerous other ways and helps by saving you before your account is emptied.
• Click Auditor: As the name suggests, Click Auditor keeps a check on all your pay per click engines and reports any suspicious activities.
• Ad Watcher: This program is used to keep a track on ROI and also helps to monitor and eliminate frauds.
• Click Detective: Using sophisticated tracking mechanisms; Click Detective determines whether a click is normal or abnormal and also has prevention tools for dealing with an abnormal click.

How to overcome Click Fraud?
Most of the pay-per-click search engines offer a credit of future clicks or reimburses the money of a victim of Click Fraud. However, a victim has to provide proper evidence of the fraudulent activities.
One survivor of Click Fraud is Ticketluck which is a resale ticket marketplace. The website was a victim of Click Fraud but quickly recovered from it employing all the preventive measures and is presently one of the best websites around for booking tickets for hot events.