Which is the best tool for keyword research?

[jasoncamroon]

Which is the best tool for keyword research?

[schumannrober]

Google adwords : no doubt this is best tool to search keywords.

[michaeljohn]

Google ad word as well as Keyword Discovery both are good.

[shaleen]

The keyword on which my site tops doesn't fetch me enough traffic. I found it on google adwords tool. I don't get even 1/4th traffic from that keyword. but google shows the global monthly and local search figure of that particular keyword in thousands.