There are but two types of keywords. Those associated with the intent to buy and those with the intent to research. Before you start the construction of a new website, before you plot your keyword strategy or before you spend PPC dollars, make sure you know which keyword type you’re using and why.
Each is different in ways to capitalize on their intent. For keywords with intent to buy, include those that can quickly lead them to your product/service page. For keyword searches that only apply to research intention, match them up with your blog and content subjects.
Though the most efficient use of keywords is when their function has a singular focus– to buy or to research–the two can co-exist. Just make sure that is your intent and plan carefully.