Keyword competition in Google Keyword Planner is a measure to determine ranking difficulty for a keyword or long tail keywords. In other words, keywords competition represents the number of advertisers who are using Google for their PPC advertisement campaign strictly.
If you are using Google Keyword Planner for your keyword research, you have got to wonder what does it mean when you see Low, Medium, or High Competition in results.
In the words of Google:
The level of competition – low, medium or high – is determined by the number of advertisers bidding on each keyword relative to all keywords across Google.<