Above is correct, but it is a little more complicated than that.
Broad match (no quotes)- I am going to buy a watermelon at the store and put in my car (I like watermelons and its hot here).
so if you look for broad search volume you are getting ALL SEARCHES CONTAINING THAT KEYWORD, no matter what else is in the string. Cool?
Phrase Match ("buy a car") Phrase match search volume is all search strings where the term buy a car appear together regardless of what other words are in typed into goregle. So go buy a car and bring me some damn watermelons would be tallied as one PHRASE MATCH search, are you with me?
Exact Match [buy a car] SEO people like us love the exact match search volume because that includes only the times someone has typed buy a car and NOTHING MORE NOTHING LESS into gaygle, so the metrics returned from shitgle are way more accurate to the actual amount of real undiluted INTEREST there really is in our target keyword.
Note that this shit is notoriously inaccurate, but its all we got so we use it as a good general tool of market value.
Kind of how we all know that Alexa rank is bullshit and adplanner is bullshit, quantcast is bullshit, EPCs are always bullshit, but again, until the super data algorithm encryption loads up the random access memory file library shit tantrum buffer we do what we can with what we got.
Hope that shit helps