Negative keywords prevent your PPC ads from appearing in search engine results. Use of these often helps your pay per click ads not to show up in search engine results for non relevant keywords. Thus, adding negative keywords not only saves your money and but also draws quality targeted traffic to your web site. Negative keywords improve the performance of your PPC advertisement in search engines.
For Example-
Pet sitters – cinema, classics, cleaning etc…
Hygiene product: reviews, travel, paints, wholesale, furniture etc…
When to use negative keywords?
Whenever you do a keyword research look for negative keywords related to that keyword, this is one of the easy steps to do it in the beginning of your keyword research which saves your time and money.
Adding negative keywords help in qualified clicks preventing unnecessary displays of your ad. Use phrase and exact match for your keyword phrases, this helps on negative keywords and increase quality traffic.