In Keyword Planner, formerly known as the Keyword Tool, you can get search volume and traffic estimates for keywords you're considering. Unfortunately, when Google transitioned from Keyword Tool to Keyword Planner, they stripped out a lot of the more interesting functionality. But you can make up for it a bit if you take the information you learn from Keyword Planner and use Google Trends to fill in some blanks.
You can use Keyword Researcher Pro with the best free keyword research tool out there, Google KW planner. Importing and exporting data is as easy as clicking a button. It’s all done at lightening speed too. There are tutorials of how to do this in video form on the sales page here and they show just how easy this tool is for finding those long tail keywords.
What are people looking for on your site? These terms are keywords in the vocabulary of your actual audience and should definitely be added to your keyword list. Do not forget to look at the keywords people filled in that didn’t get any results: this was stuff people were expecting but didn’t find. You can look into the results of your internal search in Google Analytics at Behavior → Site Search → Search Terms.
2. The second category are keyword tools based on the competition. One of the first things to determine is not only who the business competitors are, but who the SEO competitors are. Keyword research can be done by simply doing research on high-performing competitors. Some of my favorite domain-based keyword tools are SEMrush, SpyFu, and BrightEdge's Data Cube.
Are you a business owner, online marketer or content creator? If so, most likely you would like more people to visit your website, read your content and buy your products or services. The easiest way to achieve it is to find out what your potential customers or readers are searching for on Google and create content on your website around these topics.