Negative keywords are a big problem with your PPC campaign. If you could not identify the negative keywords of your Campaign this can kill your Pay Per Click Advertisement. You need to identify untargeted keywords very carefully. If you know your industry very well you can pick the untargeted ones easily.

Even today some of my Campaigns loose money on untargeted keywords you need to check your Web stats to find the keywords which is not relevant to your campaign. Every day I check my Google Analytic stats and figure out those keywords and add into the negative keyword list.

Negative keywords can bring in good click through rate but it is not going to help your PPC campaign. Negative keywords can cost you a fortune for beginners. If you’re a newbie in Online Advertisement using Pay Per Click the best advice before starting off yourself is learn from successful Pay Per Click Expert or give your start of your campaign with some good successful PPC Management Companies and master yourself slowly and read the monthly reports provided by the company and educate yourself about PPC.

One of the ways to protect you from negative keywords is use of exact and phrase match in your keywords. This could reduce the negative keywords in your campaign drastically. But the problem here is you will loose potential customers with long tail. There is a very informative post about negative keywords in Google Adwords at Webmasterworld forum called - Finding & Implementing Negative Keywords started by eWhisper. Check it out.