The goal of keyword research is to find a phrase that meets these criteria: many people are searching for it (high search volume), and you have a realistic chance of ranking relative to other sites (low competition).
Search volume—This is the popularity of the keyword. How many people are searching for the phrase? There is no point in targeting a phrase if no one is searching for it.
Competition—There is also no point in targeting a phrase if you have no chance of ranking for it. How likely is your page to rank for the phrase? How many websites are relevant for this phrase? Are they powerful sites?